This essay will attempt to flesh out some important details that affect how the doctrine of Papal infallibility, today held by all Catholics, is analyzed by Catholics and Orthodox by drawing to critical aspects of Pope Agatho’s letters that were read aloud at the 6th Ecumenical Council, that of Constantinople (681). In the dogmatic letters of Pope Agatho and the Roman Synod under him addressed to the Byzantine Emperor, and read aloud at the Council, the Pope describes his intention to uphold the Apostolic faith by sending legates to the East with his letters. The legation to the Emperor are given in words that show clearly that the doctrinal position of the Apostolic See was not up for debate, but was rather settled, leaving only that the Ecumenical Council hosted by the Empire should formally ratify the contents:
“We have directed persons from our humility to your valour protected of God, which shall offer to you the report of us all, that is, of all the Bishops in the Northern or Western Regions, in which too we have summed up the confession of our Apostolic Faith, yet not as those who wished to contend about these things as being uncertain, but, being certain and unchangeable to see them forth in a brief definition, suppliantly beseeching you that, by the favour of your sacred majesty, you would command these same things to be preached to all, and to have force with all.“Nicene and Post-Nicene Fathers, Second Series, Vol. 14
This comes out more in a specific threat from the same letter:
Whichever of the bishops wishes to preach sincerely together with us what is contained in the profession of our lowliness regarding our apostolic faith, we receive them as of one mind with us, as fellow-priests, fellow-ministers, as having the same faith, and to speak clearly, as our spiritual brothers and fellow-bishops. But those who do not wish to make this profession of faith with us, we judge them, as enemies of the catholic and apostolic profession of faith, to be liable to eternal condemnation. Nor would we ever receive them ever in the college of our lowliness, unless they have amended. Nor should any of them suppose that we have transgressed against what we have received from those who have gone before us. (Mansi 11.297 AB; Eng. Trans. Fr. Patrick O’Connell, S.J., The Ecclesiology of St. Nicephorus 758-828: Pentarchy and Primacy (Roma: Pont. Institutum Studiorum Orientalium, 1972), 187)
Bishop Vincent Gasser (1809-1879) used the dogmatic epistles of Pope Agatho as examples of the scenario where there is a “previous dogmatic epistle” of the Pope sent for the Council to give its full adherence and ecumenical ratification (c.f. O’Connor, The Gift of Infallibility, 42-43). For Agatho and his Synod, the matter was already dogmatic due to his predecessor Pope Martin I and his synodal condemnation of Monotheletism. As Ed Siecienski notes, in the Pope’s mind, “there could be no doctrinal debate since the matter had already been decided at the Lateran Synod” (c.f. The Papacy and the Orthodox, 205). Even the famous conciliarist theologian Jacques-Bénigne Bossuet (1627-1704), in his commentary on the 6th Ecumenical Council provided by the NPNF series on New Advent states that, from the perspective of the Roman See, “they defined the matter.” In the Pope’s personal letter to the Emperor, he makes the following claim:
And therefore I beseech you with a contrite heart and rivers of tears, with prostrated mind, deign to stretch forth your most clement right hand to the Apostolic doctrine which the co-worker of your pious labours, the blessed apostle Peter, has delivered, that it be not hidden under a bushel, but that it be preached in the whole earth more shrilly than a bugle: because the true confession thereof for which Peter was pronounced blessed by the Lord of all things, was revealed by the Father of heaven, for he received from the Redeemer of all himself, by three commendations, the duty of feeding the spiritual sheep of the Church; under whose protecting shield, this Apostolic Church of his has never turned away from the path of truth in any direction of error, whose authority, as that of the Prince of all the Apostles, the whole Catholic Church, and the Ecumenical Synods have faithfully embraced, and followed in all things; and all the venerable Fathers have embraced its Apostolic doctrine, through which they as the most approved luminaries of the Church of Christ have shone; and the holy orthodox doctors have venerated and followed it, while the heretics have pursued it with false criminations and with derogatory hatred.New Advent
According to the Pope, the Apostle Peter continues to fulfill his “duty of feeding the spiritual sheep of the Church”, and the way he has done it is by providing a “protecting shield” to the teaching ministry of the Apostolic See of Rome. Consequently, Rome had “never turned away from the path of truth in any direction of error.” Moreover, Rome carried the authority of St. Peter, and this authority had been followed by the entire Catholic Church, the Ecumenical Councils, and the venerable Fathers of the Church since the beginning. The Pope goes on to explain how the divine promise of Jesus Christ to St. Peter for unfailing and unerring faith also applies to the Apostolic Pontiffs of the Roman Church:
For this is the rule of the true faith, which this spiritual mother of your most tranquil empire, the Apostolic Church of Christ [of Rome], has both in prosperity and in adversity always held and defended with energy; which, it will be proved, by the grace of Almighty God, has never erred from the path of the apostolic tradition, nor has she been depraved by yielding to heretical innovations, but from the beginning she has received the Christian faith from her founders, the princes of the Apostles of Christ, and remains undefiled unto the end, according to the divine promise of the Lord and Saviour himself, which he uttered in the holy Gospels to the prince of his disciples: saying, Peter, Peter, behold, Satan has desired to have you, that he might sift you as wheat; but I have prayed for you, that (your) faith fail not. And when you are converted, strengthen your brethren. Let your tranquil Clemency therefore consider, since it is the Lord and Saviour of all, whose faith it is, that promised that Peter’s faith should not fail and exhorted him to strengthen his brethren, how it is known to all that the Apostolic pontiffs, the predecessors of my littleness, have always confidently done this very thing: of whom also our littleness, since I have received this ministry by divine designation, wishes to be the follower, although unequal to them and the least of all.New Advent
Here the Pope repeats the bold claim that the Roman Church had never erred from the Apostolic tradition but has, since its founding with both Peter and Paul, remains “undefiled unto the end, according to the divine promise of the Lord and Saviour himself.” You couldn’t get a clearer claim to infallibility than this. The promise of never-failing faith which equips Peter to strengthen the brethren continues in the Apostolic Pontiffs of the Roman episcopate, which is a divinely designated “ministry” held by Agatho at the time of the letter. If there was any doubt that this was a claim to the infallibility of the Roman See by Agatho’s reference to the “Apostolic Church of Christ,” let another section of the same letter resolve that matter:
Therefore the Holy Church of God, the mother of your most Christian power, should be delivered and liberated with all your might (through the help of God) from the errors of such teachers, and the evangelical and apostolic uprightness of the orthodox faith, which has been established upon the firm rock of this Church of blessed Peter, the Prince of the Apostles, which by his grace and guardianship remains free from all error, [that faith I say] the whole number of rulers and priests, of the clergy and of the people, unanimously should confess and preach with us as the true declaration of the Apostolic tradition, in order to please God and to save their own souls.New Advent
So here, the “Holy Church of God” is a reference to the universal Church. But notice the next reference to Church is “this Church of blessed Peter.” Thus, there is a reference to the universal Church and the Roman Church all in one sentence, and the logic of the argument is as follows: the universal Church should be cleansed of all errors by the light of the true faith which is established upon the rock of Peter’s Church, i.e. the Roman Church, “which by his grace and guardianship remains free from all error.” So you have three times where Pope Agatho speaks of the Roman Church is free from all error and had never, nor ever will, turn away from the truth on the grounds of a miraculous guardianship. The Pope senses the obligation to pronounce his position of authority and speaks of this as a special ministry of Peter. Very clearly then, Agatho sees the Roman episcopate as carrying the Petrine ministry that also visualizes the Petrine communion. In another plea for the Church of Constantinople to become firm in the true faith, the Pope states:
…but desiring them with outstretched spiritual arms, and exhorting to embrace them returning to the unity of the orthodox faith, and awaiting their conversion to the full rectitude of the orthodox faith: that they might not make themselves aliens from our communion, that is from the communion of blessed Peter the Apostle, whose ministry, we (though unworthy) exercise, and preach the faith he has handed down, but that they should together with us pray Christ the Lord, the spotless sacrifice, for the stability of your most strong and serene Empire.New Advent
On the contrary, Pope Agatho thinks the See of Constantinople had been tainted with error:
Wherefore the predecessors of Apostolic memory of my littleness, learned in the doctrine of the lord, ever since the prelates of the Church of Constantinople have been trying to introduce into the immaculate Church of Christ an heretical innovation, have never ceased to exhort and warn them with many prayers, that they should, at least by silence, desist from the heretical error of the depraved dogma, lest from this they make the beginning of a split in the unity of the Church.New Advent
Agatho even threatens the Patriarch of Constantinople with everlasting damnation if he does not agree with the Roman confession of faith:
Moreover, most pious and God-instructed sons and lords, if the Archbishop of the Church of Constantinople shall choose to hold and to preach with us this most unblameable rule of Apostolic doctrine of the Sacred Scriptures, of the venerable synods, of the spiritual Fathers, according to their evangelical understanding, through which the form of the truth has been set forth by us through the assistance of the Spirit, there will ensue great peace to them that love the name of God… But if (which God forbid!) he shall prefer to embrace the novelty but lately introduced by others… despite the exhortation and admonitions of our predecessors in the Apostolic See, down to this day, he himself should know what kind of an answer he will have to give for such contempt in the divine examination of Christ before the judge of all.New Advent
So we see in the above pronouncements in the Pope’s dogmatic epistle the following claims. The Roman See is (1) the supreme Church belonging to St. Peter, (2) inherits the “authority” and “ministry” of Peter, (3) that the duty of shepherding the lambs of Christ given to St. Peter, and the promise of unerring and unfailing faith has been divinely maintained by his ministry which is stationed in the Roman bishopric, and (4) has been and will be perpetually guarded from error by Christ’s promise. Over this Roman episcopate, Peter continues to guard with his protecting shield his successors from ever departing from the Apostolic tradition. When these letters from Rome were finally read aloud, the Patriarch of Constantinople said at the Council:
I have diligently examined the whole force of the suggestions sent to your most pious Fortitude, as well by Agatho, the most holy Pope of Old Rome, as by his synod, and I have scrutinized the works of the holy and approved Fathers, which are laid up in my venerable Patriarchate, and I have found that all the testimonies of the holy and accepted Fathers, which are contained in those suggestions agree with, and in no particular differ from, the holy and accepted Fathers. Therefore I give my submission to them and thus I profess and believe.New Advent
Following him, all the Bishops under the Patriarchate of Constantinople likewise solemnly declared their agreement with the letters of the Pope. And yet, the Council also comes to the following conclusion about one of the predecessors of Pope Agatho:
And with these we define that there shall be expelled from the holy Church of God and anathematized Honorius who was some time Pope of Old Rome, because of what we found written by him to Sergius, that in all respects he followed his view and confirmed his impious doctrines.New Advent
There is no mistaking the fact that the Council in Constantinople examined the letter of Pope Honorius to Sergius and found that he “followed” the “view” or Sergius and “confirmed his impious doctrines.” Therefore, they judged him excommunicate and anathematized, albeit posthumously, because he purportedly held the error of Monotheletism. The Pope who received the finished Acts of Constantinople III wrote in return to the East the following:
My predecessor, Pope Agatho of Apostolic memory, together with his honorable Synod, preached this norm of the right apostolic tradition. This he sent by letter to your piety by his own legates, demonstrating it and confirming it by the usage of the holy and approved teachers of the Church. And now the holy and great Synod, celebrated by the favor of God and your own has accepted it and embraced it in all things with us, as recognizing in it the pure teaching of the blessed Peter, the prince of the Apostles, and discovering in it the marks of sound piety. Therefore the holy and universal sixth synod, which by the will of God your clemency summoned and presided, has followed in all things the teaching of the Apostles and approved Fathers. And because, as we have said, it has perfectly preached the definition of the true faith which the Apostolic See of blessed Peter the Apostle (whose office we unworthily hold) also reverently receives, therefore we, and by our ministry this reverend Apostolic See, wholly and with full agreement do consent to the definitions made by it, and by the authority of blessed Peter do confirm them, even as we have received firmness from the Lord Himself upon the firm rock which is Christ…New Advent
He goes on to speak of the heretics condemned at the synod:
And in like manner we anathematize the inventors of the new error, that is, Theodore, Bishop of Pharan, Sergius, Pyrrhus, Paul and Peter, betrayers rather than leaders of the Church of Constantinople, and also Honorius, who did not attempt to sanctify this Apostolic Church with the teaching of Apostolic tradition, but by profane treachery permitted its purity to be polluted. (Citation from John Chapman, The Condemnation of Pope Honorius, para. 25, p. 112-15)
Therefore, even the Pope assented to the fact that one of the occupants of Peter’s throne had been guilty of doctrinal heresy. Now, let us set aside the question of whether the Council must be unmistaken as to the question of facts surrounding the inward heart and mind of Honorius upon his last breath before departing this life. For my purposes here, it will only be worth recognizing that the Council, both Head and Members, agreed to process a charge of heresy against one of the successors of St. Peter, and one of the predecessors of Pope Agatho.
Now, this scenario puts both Catholics and Orthodox in a difficult position. Let me explain why this is a difficulty for Catholics first. For starters, Pope Agatho’s claim of Roman indefectibility seemed to be general and all-embracing. In other words, it seems to be that he thought the Roman See, per the promise of Jesus to Peter, would be protected from error always and forever. Honorius’s condemnation, prima facie at the very least, refutes this idea. Since the Papal claims of Agatho are extremely grand, their veracity depends on their being 100% true. It only takes one failure for Agatho’s claims to be falsified. A bold declaration that the Roman See has never had a heretical occupant would be equitably disproved by one single heretical occupant. But since, as it turns out, the Council decided a heretic had occupied Roman episcopate, all of the claims of Agatho are now, at the very least, called into question. This is especially so because Agatho claimed that the Roman see had never departed from the Apostolic faith whereas Constantinople had, and the latter had done so by its Bishop subscribing to errors. It stands to reason that a mere formally heretical bishop of Rome would also forfeit the attribution of being free from all error. We can be certain that Agatho gave no evidence of an ex cathedra versus extra cathedram distinction when he made these claims. More on that below.
Let me now describe the problem for the Orthodox. First, the Orthodox Church has a high view of Ecumenical Councils. Their decrees and official pronouncements are considered God-breathed and ipso facto to be revered as the very words of God. For them, when an Ecumenical Council receives a certain letter by a solemn acceptance, that letter enters into a dogmatic patrimony of the Church’s treasury. For example, the special letter written by the Patriarch St. Sophronius on the two wills and operations of Christ was accepted into the
dogmatic epistolary of the Council: “We have also examined the synodal letter of Sophronius of holy memory, some time Patriarch of the Holy City of Christ our God, Jerusalem, and have found it in accordance with the true faith and with the Apostolic teachings, and with those of the holy approved Fathers” (New Advent). The letters of Pope Agatho were especially accepted by everyone without alteration by the Council. After scrutinizing the letters, the council Fathers ratified them solemnly very much like the Council of Chalcedon ratified Leo’s Tome. The bishops describe Agatho’s letter in their own letter to the Emperor: “For the ancient city of Rome handed thee a confession of divine character, and a chart from the sunsetting raised up the day of dogmas, and made the darkness manifest, and Peter spoke through Agatho…” (New Advent). It simply cannot be argued that the Greeks had objections to these letters. Otherwise, they would have stalled acceptance for the sake of erroneous content. Consequently, if one sees the 4 points adduced from the letters of Agatho above, it can be easily seen how an embrace of those points by a dogmatic modality of the Eastern Orthodox Church can be problematic. The Orthodox do not accept the supremacy or infallibility of the Roman See as the See of Peter, and yet they have here a dogmatic epistle infused into its dogmatic archives which boldly and unmistakably makes those claims.
Some might say that the Byzantines simply read those Papal claims of Agatho as acceptable hyperbolic self-aggrandizement on the part of the First See to be interpreted as simply grandiose literary fiction. In other words, they were to be read as purposefully stretching reality. However, there are some difficulties with that position. For one, Agatho certainly did not intend to be unrealistic. How do we know that? Because Agatho stated explicitly that Peter’s protecting shield had the effect that Rome “never turned away from the path of truth in any direction of error” and that his predecessors “always confidently” strengthened the brethren under the promise of Jesus which stated “I have prayed for thee, that they faith fail not. And when thou art converted, strengthen thy brethren.” The Roman see “never erred from the path of the apostolic tradition, nor has she been depraved by yielding to heretical innovations, but from the beginning… and remains undefiled unto the end, according to the divine promise of the Lord and Saviour himself…” In other words, he understood that the divine protection from error provided for the Roman See by Peter’s shield proved itself in the concrete infallibility of the occupants of Peter’s chair in history since the beginning. He says his predecessor never yielded to heresies, and that was a result of the promise of Jesus. He also says this very same protection will last “unto the end”, and thus the expectation is that the future will certainly match the historical infallibility of the Popes hitherto the time of Agatho, which amounts to a perpetual infallibility of Roman bishops until the end of time. Therefore, these Papal claims are not fictitious self-aggrandizement, but quite literal and obviously real. It perfectly matches the claims made in the earlier Formula of Hormisdas (519) which said the Apostolic See is the foundation and security of the Christian religion since the Apostolic faith had been held by it without spot or blemish since the beginning. That is a historical claim, and therefore a realistic claim. One might say the Greeks might have had a more flexible reading, but this lacks any compelling evidence given the clarity of the meaning and intention of the Pope by the foregoing reasons. The claims are unmistakable.
As it looks, both the Orthodox and the Catholic have some challenges with the presence of a heretical Honorius. Is there a solution to this puzzle? In my opinion, the Orthodox have no option other than to say that the Papal claims of Agatho are simply wrong and to be rejected. In fact, in formal services where the Orthodox receive converts to her fold from Catholicism, the converts are explicitly asked if they will renounce papal infallibility, which is yet clearly in Agatho’s letter. The Orthodox might offer some sort of conditional explanation, such as the Popes of Rome are infallible insofar as Peter’s speaks through them, but that is to be determined not by the Pope himself but by his Bishops who examine, test, and verify the truth of his decrees. But such a process is redundant because the real authority in that case would be the verification-act of the Bishops, and not the Pope himself. Everyone can be said to have spoken “without error” if what it takes to arrive at that decision is the Bishops unanimously testing and verifying that the spoken word is truly without error in their own judgment.
It would be like a student handing in a test for grading. If the teacher, who himself knows the right answers, grades the test and judges it to be an A+, then the student is acclaimed to have been without any error, but by the judgment and authority of the teacher. This kind of interpretation depletes the whole impetus behind Christ’s promise as cited by Agatho, namely, that it would be Peter who does the authoritative protecting and strengthening of the brethren, not the other way around. The logical edifice upon which the Peter-to-Church architecture rests is that Peter is the founding support of strength to protect the Church which is built off of it. To turn it around and say the building supports the foundation runs into a logical problem, and it reduces Agatho’s claims to an absolute redundancy.
The Orthodox often appeal to the Peter-to-Church architecture as compared with the Head-to-Members construct of Apostolic Canon 34. In that canon, it is stated that a regional head (i.e. the Metropolitan) should not enact or execute decisions without the agreement of the Members (Regional Bishops), and the Members, likewise, must not enact or execute decisions without the approval of the Head. Neither the Head or the Members can go past each other, and both are equally accountable to the other. This is precisely what is meant by “first among equals”. The only prerogative that the Head has which can be measured to be superior to the Members is that when and if the majority of Members wish to execute decision X while the Head judges otherwise, you have the Head serving as a barrier to the execution of a decision agreed upon by the majority. As cited above, the claims of Agatho are clearly beyond the construct of Apostolic Canon 34. In the first place, that canon doesn’t explicitly speak to the Prima Sedes (First See), but to the regional Metropolitan. Secondly, Agatho clearly said that he sent his legates to Constantinople not to contend with the content of the faith drawn up by the Roman synod but for the purpose of seeing it be defined openly in an Ecumenical Council. On top of that, he claimed the doctrine of the Apostolic See to be divinely infallible per the promise of God. There could not be a more clear indication that Agatho did not think he was bound by the restriction placed on the Head in Apostolic Canon 34.
Now, the Catholic also has an uphill battle with the Honorius situation. The difference between the Catholic and the Orthodox, however, is that the Catholic has a chance at maintaining the correct-ness of Agatho’s letter as well as absorbing the consequences that come with the anathema of Honorius as a heretic. This chance is provided by what later would be called the ex cathedra mode of Papal teaching. Before explaining what that is and why is qualifies as a bridge of continuity with Agatho’s letter, it is worth pointing out that if one reads Pope Leo II’s ratification of the 6th Council quoted above, he does not see the fact of a heretical predecessor in the Apostolic See to have hindered his understanding of the authority of his office in any way. Right in the midst of including Honorius as one of the heretics anathematized by the Council, Leo still says that he holds the authority of Peter to confirm the Council by the divine assistance of Peter the rock. Moreover, even the Greek bishops, after having included Honorius in their list of excommunicated names, still held that the Apostolic See is responsible of confirming the Council on the basis of its Petrine authority: “Therefore to thee, as to the bishop of the first see of the Universal Church, we leave what must be done…” Therefore, both Pope Leo II and the Greek bishops did not believe Honorius’s error impugned the lawful continuance of the unique ministry of the Apostolic See. In particular, they did not think the Honorius event abrogated the Petrine protection from the Roman See either, for in the letter of the Greek bishops to the Emperor, they saw the dogmatic epistle of Agatho as divinely inspired by Peter.
It is also worth pointing out that Honorius’s successor, John IV, wrote an extensive apology defending his predecessor from the charge of holding the Monothelite heresy. I have to say, from my own reading of Pope Honorius’s letters, I find that he is nowhere near the Monothelite error, and John’s apology is convincing. Popes Theodore, Martin, and certainly Agatho obviously thought Honorius was orthodox, and St. Maximus the Confessor defended Honorius all the way to his dying breath. Some scholars have tried to say that Pope Leo II did not condemn Honorius for heresy but for pastoral negligence, but the case for that seems rather flimsy, especially since Leo II did not make any formal correction of the Council’s anathema to Honorius specifically for what they found in his letters. Nevertheless, the objective wording used by him which says, in so many words, that Honorius failed to extinguish the flames of heresy through his negligence. What is rather interesting is that, in the 9th century, the famous Papal librarian Anastasius (810-878) held that accepting the Council’s anathema of Honorius was not necessarily binding, and contented himself with the apology of John IV. He writes this concerning the events surrounding Honorius:
“… there came into my possession the apology of the Roman pope, John IV, on behalf of Pope Honorius who was attacked by false accusers because he had written about only one will of our Lord Jesus Christ. This apology indeed makes it excusable enough, I believe, although the sixth holy council declared the anathema on him as if he were a heretic. And it pierced with the weapon of reproach him who was placed in the judgment of God alone, since a heretic springs not so much from the deceit of errors as from a wrong choice and an opinion that is argumentatively obstinate. But meanwhile, who is there amongst us who can say whether he dictated the letter from which his accusers took the kindling for his anathema, since such a thing could also have happened by either the scribe’s lack of discipline, or from hatred towards the Pope?… nothing other seems to be commanded by the great teachers of the Church than that we give the benefit of the doubt in interpreting those deeds when the spirit in which they were done is not known…. It is rash to judge them, and particularly rash to condemn them… But lest we seem to be making an accusation against a council so holy and venerable, or to criticise it carelessly, we think it fitting for us to consider them in the way we know our holy fathers considered the great council of Chalcedon. One of them, namely holy Pope Gregory, indicated that this was to be accepted only ‘up to the issuing of the canons’… But look, while our wordy preface is being directed to you, we have retreated far from my work of translating, digressing to show that in the rock of the apostolic see , as far as the faith is concerned, not even through the agency of Honorius has there been found any trace of the serpent, that is, of the virulent sect. Therefore accept the already mentioned apology of Pope John for Honorius. Accept the apology for the same Honorius from the excerpted letter of Maximus the Monk and truly a philosopher and martyr for Christ our God, sent to the priest Marinus.” (Seventh-Century Popes and Martyrs: The Political Hagiography of Anastasius Bibliothecarius (Turnhout, Belgium: Brespols, 2006), 151-157)
Such is a 9th century resolution of Roman infallibility and the Honorius event. Later in the same century, Pope Hadrian II conceded that while the Greeks condemned Honorius, that judgment carried no force until the Apostolic See confirmed it, as was done by Pope Leo II. From there you have an awareness of the distinction between the personal versus official infallibility of the Roman Pontiff in theological science. While it would be the easiest, so far as the content of Honorius’s letters are concerned, to defend him against the error of Monotheletism, I’m more interested in taking the position, for the sake of argument, that the Council’s judgment was correct. I do this especially since the Eastern Orthodox are obliged to believe the Council’s decision even against what might be seen from the letter or from the defenses of Honorius by the Popes of Rome, even Maximus. What might be said for the Catholic position of Papal infallibility in light of a heretical and anathematized Honorius? What does this say of the perfect purity of the Apostolic See in light of Peter’s shielding protection? While the Orthodox seem to have only one option, namely, that Agatho and the Council were speaking in hyperbolic terms, an option which I’ve excluded in light of the literary evidence, the Catholic has the option of proffering a development of doctrine in the modality of Papal teaching. This development begins with looking more closely at the nature and function of the Petrine office. And here we return to the ex cathedra conditionality introduced above.
Is it the case that the Pope must be always free and immune from error? I think it is eminently reasonable to admit that a Pope, when he exercises himself as a private person, is just as open to erring as any human being. The Petrine shield would not activate in that case because the Petrine office isn’t being exercised. As a private person, the Pope acts and speaks as an equal to all other persons, and, as Cardinal Cajetan apt said, an equal can’t authoritatively bind and equal. So, when is the Pope exercising the Petrine office? The Catholic Church came to understand that this infallibility becomes guaranteed to be active when the Pope exercises his universal office. If Peter is the foundation of the universal Church, Peter is a universal support, and so it would be requisite for the Pope to be addressing the whole flock of Christ to exercise his full Petrine gift of infallibility. The late Dom John Chapman stated this concept very well:
Infallibility is, as it were, the apex of a pyramid. The more solemn the utterances of the Apostolic See, the more we can be certain of their truth. When they reach the maximum of solemnity, that is, when they are strictly ex cathedra, the possibility of error is wholly eliminated. The authority of a Pope, even on those occasions when he is not actually infallible, is to be implicitly followed and reverenced. That it should be on the wrong side is a contingency shown by faith and history to be possible, but by history as well as by faith to be so remote that it is not usually to be taken into consideration. (The Condemnation of Pope Honorius, 111).
In short, since the Pope is empowered to teach the universal Church in a binding manner, such that it could not invite any dissent whatsoever, it must be that the Pope’s teaching is preserved from errors that would abrogate the universal Church’s commitment to belief in the truth. And so, one can see how the infallibility of the universal Church is what grounds the infallibility of Papal teaching. Taking from this, if one reaches back and re-read Agatho’s letter with this greater light, then what you have is a development in doctrine in that, while Agatho thought the Petrine protection was like a protective umbrella on all teachings from the Apostolic See, it is better seen later that there is some capacity for Papal teaching to fail, and that is when it is not written dogmatically with the intention to bind the whole Church. Honorius’s letter to Sergius was far less than dogmatical, and they even less sought to bind all believers to the subscription of one will in Christ. Now, the reader my object that this sounds like an ex post facto revision to manufacture consistency. More on that further below.
Does this explanation suffice to explain how Leo II and the Council still recognized the Petrine ministry as active during their time while also recognizing that a heretic sat on Peter’s chair 40 years prior? I sincerely doubt they were working with an ex cathedra versus extra cathedram distinction, but they certainly recognized that the Pope was divinely protected in one set of conditions (Agatho’s decree) while in other conditions was allowed to fail (Honorius’s letter). I think what we see are (1) clear attestations of Roman infallibility and (2) a case of a failing Roman Pontiff, a conundrum which would only be resolved by later theological development. Now the deeper question here is whether the Petrine charism is expected to have come out from Papal decrees a priori or a posteriori. I think that distinction spells out the difference between how an Orthodox and a Catholic reads this data. For the Orthodox, as already described, only when the Pope’s decrees have been examined, tested, verified, and universally received by solemn acclamation can it be known that the decree was inerrant. On the other hand, the Catholic understands that when the Pope exercises his office of universal teacher and pastor of all Christians, the decree is both infallible and irreformable simply by virtue of the Pope’s authority and requires no ex post facto verification. Consequently, the a priori vs. a posteriori distinction makes all the difference in the world, since the latter allows for a set of circumstances where perpetual dissent, rejection, and even excommunication from the Pope of Rome is compatible with the design of Christ’s Church. Ergo, the Eastern Orthodox today have feel no injury to the integrity of the Church by their severance from the Apostolic See for 1,000 years now. On the other hand, Catholics are taught that ex cathedra decrees, or those decrees even which the Pope gives as indicating the universal belief of the Church through its universal and ordinary magisterium, cannot contain errors ipso facto.
The question is what does the evidence support? Well, as we’ve seen, the theoretical claims of Agatho clearly support the a priori position since he understood the cause of the infallibility of the Roman Pontiffs to be in the divine help of St. Peter to whom Christ our God promised such infallibility. On the other hand, the Orthodox have a strong case in that they can point to Honorius as an instance of failure, and all it takes is one failure to convince everyone that Papal decrees can’t be taken for granted. However, by effectively allowing 1,000 years of persistent heresies from St. Peter’s See, their conviction has painted an altogether different picture that is accepted by the 6th Council’s solemn acceptance of Agatho’s claims. How can one seriously read the claims of Agatho, which merely echo the claims in the Formula of Hormisdas, and come away thinking that the essence of the Church remains intact while indefinitely severed from the communion of Peter’s see? It simply is incongruent with the most reasonable reading of the texts accepted by the Council. The development of Catholic doctrine on the conditions of the Papal magisterium allow for a maintenance for the substance of Agatho’s claims about Peter’s See while also making exceptions for the allowance of Papal failure, whereas the Orthodox resolution has been, since the schism, to completely question the validity of Agatho’s claims in both substance and theory altogether.
In conclusion, the letter of Agatho read and solemnly accepted by the 6th Ecumenical Council held in Constantinople (681) serves as a quasi-litmus test for the coherence and credibility of Catholic and Orthodox positions on the position and authority of the Roman Pontiff. As shown, Agatho clearly made claims to a divinely promised and supernaturally fixed supremacy and infallibility of the successors of St. Peter in the Roman episcopate. These claims were interpreted by Agatho himself to be literal and historical, as well as futuristic, as he held the promise of indefectibility would be pertain to the Roman see until the end of time. The Ecumenical Council read Agatho’s letter and found it to be divinely inspired and wholly orthodox, as written by Peter himself. The dogmatic status of this letter, as was shown, serves to be a bit of a dilemma for both Catholics and Orthodox. The Orthodox today reject the claims of Agatho, and the Catholic Church after Honorius had to develop her understanding of the Petrine protection that covers the magisterium of the Roman Pontiff. Both the Orthodox rejection and the Catholic development can be seen as some kind of alteration of interpretation. The Orthodox reject the Agathon claim to divinely perpetual infallibility and have re-interpreted the Petrine primacy as rigorously conditional upon factors that have now disqualified Rome from being a functional part of Christ’s Church for 1,000 years now. That clearly clashes with the Papal claims of Agatho. On the other hand, where Agatho claimed complete and total protection to papal teaching, the Catholic Church has had to bring a distinction between not only personal versus official infallibility, but even a distinction between official fallibility versus official infallibility, i.e. the ex cathedra versus extra cathedram distinction. This is because Honorius’s letter to Sergius which was condemned as erroneous was some level of official teaching on the part of the Roman Pontiff.
The Orthodox reinterpretation of the Petrine primacy along the lines of Apostolic Canon 34 was shown to be discordant with the Agathon epistle, and as such, helps in nowise to reconcile contemporary Orthodoxy with the 6th Ecumenical Council. The relegation of Peter to the function of the Metropolitical Head of Apostolic Canon 34 reduces Peter to prima inter pares (first among equals), accountable to the Members of the region, i.e. the Bishops gathered in an Ecumenical Council. From the get-go Agatho’s epistle made it clear that there was no room for debate since the matter was settled, whereas the Orthodox wish to interpret Papal decrees as worthy to be honored, but ultimately tested and graded by the authority of a Council.
Catholic theologians have had to introduce this distinction between official fallibility and official infallibility, which also is a possible cause for some serious problems. If the official magisterium of the Roman Pontiff can still err if it is not an exercise of his supreme and universal office as teacher and pastor of all Christians, then that seems to open a wide window of possibly erroneous doctrine in the corpus of Papal teachings. Furthermore, what is the precise line dividing that hair-less-than-ex-cathedra-Papal-decree from an authentic ex-cathedra-Papal-decree? It is no secret that Catholic theologians are on opposite sides of how many ex cathedra decrees actually have occurred. At the 1st Vatican Council, you had some holding that there were a very small number of ex cathedra decrees and others, like Bishop Gasser, the author of the famous relatio on Papal infallibility himself, who thought there were “thousands upon thousands.” Some Catholics today think there have only been two ex cathedra decrees in the expanse of 2,000 years of Catholic history, and that, just within the tail-end of the last 150 years. And so, this distinction to help explain past Papal failures and what constitutes a true infallible decree may not have been as helpful as once thought. With some of these questions being almost undiscernible, perhaps as difficult as finding a needle in a haystack, Catholic theology can almost appear to have run into its own reductio ad absurdum by allowing theological wars between Catholics over what is infallible versus fallible, the very detriment that the infallible office of the Roman Pontiff was supposed to squelch in the first place. But I think there is some relief from this if one can understand that the ex cathedra mode of Papal teaching really just is the exercise of the Pope’s office towards all Christians on a matter of faith or morals to be held de fide or definitively (as part and parcel with the Apostolic deposit, divine revelation, dogmatic fact, or secondarily infallible). The intention is to bind the conscience to a doctrinal definition, the scope is all members of the Church, and the content is faith. Even so, I happen to think the Magisterium of the Catholic Church is responsible at present to make it more clear as to precisely when Papal decrees are challengeable versus when they are not. As soon as you present a mode of fallibility, theologians will think challenge-ability. And yet, as is proven by recent decrees from Rome, the faithful, nor theologians, are permitted to openly dissent from even the non-infallible teachings of the Pope (c.f. Donum Veritatem). But here’s the problem. If there is an error from the official magisterium of the Roman Pontiff, as there was from Honorius, what are the other Bishops and faithful to do if they, in their own conscience and understanding, the Pope is manifestly wrong? If we say they are to submit anyway, against their clear understanding, then one would be asking them to contradict an essential element of divine revelation. Even Donum Veritatem spells out that there may be certain conditions where one simply can’t offer their assent, and this must be regulated appropriately according to that document. However, this process can become more difficult when, as members of the Society of St. Pius X believe, constant dubia and appeals are sent to the “erring” Roman Pontiff in order to require retraction and correction and are left ignored or unsatisfied. Members of the SSPX simply say that the situation has arisen to a point where they must resist the Roman Pontiff “to his face” and make all sorts of appeals to conditions for justified disobedience to the Pope’s official, albeit fallible, magisterium.
And so, the fallible versus infallible distinction between official decrees of the Pope has now opened the way for “justified” schisms within the one Catholic fold. The alternative has been for this idea that the faithful are “safe” to hold to the errors taught in a somewhat binding manner by the Roman Pontiff, since God will not punish the faithful for doing what they are obliged to do for the sake of unity and obedience to the Papal office. The problem with this view is that it suffers from ahistoricism and it falls prey to having succumbed the members of the Lord’s body to holding to erroneous beliefs. The attempt to alleviate the dreadful consequences of heresy upon the faithful for their subscription to fallible errors from the official magisterium of the Pope sounds like an admission that the Church can become grossly contaminated with errors. Adding that the faithful won’t suffer the consequences of injuring their union with Christ might escape a full-blown apostasy of the Church, something impossible, but it suffers from being a glaring technicality with no precedent other than pure crafty reason itself. It also appears to be inconsistent with the Scriptural warning of Scripture according to Paul: “But even if we or an angel, from heaven, preach any other gospel to you than what we have preached to you, let him be accursed (anathema)” (Gal 1:8). But according to the safe-error theory, if the Pope comes along and preaches “another gospel” to us in his official non-infallible reformable magisterium, we are bound to accept it with the assent of our minds and wills? And here is where, unfortunately, Catholic communities such as the SSPX, or non-Catholic communities such as the Eastern Orthodox, strengthen their position in light of how absurd it is to find oneself in this fatal pitfall. On the other hand, if one says that “manifest errors” of the Pope’s official magisterium can be openly dissented from on the basis of a higher authority, such as remote magisterium of the past (past decrees of Ecumenical Councils or Papal ex cathedra decrees), then this could run the risk of another form of “justified” resistance that could potentially form an internal schism within the Church. It would appear the Orthodox, at least, have a more consistent understanding of what must be done in the case of an erring Pope, especially one who is informed and accused but who remains obstinate, and that would simply be for the Bishops to remove the Pope from their communion. Even the recognize-resist paradigm of communities such as the SSPX are left bound to remain in communion with a Roman Pontiff that they think is manifestly in error, and possibly a formal heretic. They often believe that only an imperfect Council of Bishops can exercise some sort of ministerial function to warn the Pope of his errors, and then, if the Pope rejects them, announce that he has forfeited his own office against his will.
Therefore, if the Catholic is going to admit that Honorius was a heretic as the 6th Council specifies, this opens the door to the capacity of a Pope to err in his official magisterium, albeit the non-infallible magisterium. And the consequence of this is that a validly reigning Roman Pontiff can possibly exercise his magisterium to contaminate the body of Christ with errors. A further consequence of this is that the Bishops of the Catholic Church, including the faithful, might find themselves in a situation where they are forced to recognize the authority and position of a Pope who might be unworthy of his office, and then this may revert the Church to a situation where the Members have to intervene and take action to announce the self-deposition of the Pope, a situation which itself has further problems in terms of what kind of superior authority would be required to challenge an erring Pope who refuses to be corrected and refuses to resign his office. That is a detrimental situation that many theologians, such as Robert Bellarmine and Francisco Suárez, simply thought the gracious providence of God would not allow in light of the promises of God to Peter and the well-being of the visible Church. And if it can happen in one Pope, i.e. Honorius, then one might press that this can happen with all Popes. Pretty soon, the whole concept of the Petrine foundation of the Church as described by the 1st Vatican Council can lose its credibility in light of too many real incongruities.
In the end, the Catholic and the Orthodox have to square their belief systems with the dogmatic epistle of Agatho. The contemporary Orthodox seem to be the most at odds with since they universally reject Papal infallibility and supremacy, and majorly reject even a universal Petrine primacy. The Catholic has to admit the Roman Pontiff can disturb the health of the faithful by officially teaching errors, and that the Petrine shield of protection that Agatho speaks of is strictly conditional to the Pope’s ex cathedra decrees. That distinction seems to be implicitly held by Pope Leo II who ratified the condemnation of Honorius, and theologians since the 7th century have had to justify the slight condition of resistance to duly reigning Roman Pontiffs. As already referenced, Pope Hadrian II justified inferiors resisting superiors when the superior is in the commission of doctrinal violations. Western Canon Law influenced by Gratian held that the Prima Sedes (First See) cannot be judged by anyone unless the Pope be found deviating from the faith. In that case, there is a painful way to a possible deposition of the Pope in the manner above described. Such a puncture to the visible health of Christ’s Church is significant, especially since breaking communion with a validly reigning Pope, even one who in open and obstinate error, is never permissible. While this is admitted by the majority of Catholics as a possibility, it is at least more in compatible with the Agatho’s letter than the Orthodox reinterpretation of it.
 Some have thought that by describing “church” here as the “spiritual mother” of the Empire, it must be a reference to the universal Church, and thus the whole section is simply speaking about the infallibility of the whole Church under the promise of Christ. However, this won’t stand up to scrutiny. The very first time “church” is described as a “spiritual mother” is a clear reference to the Apostolic See of Rome. Agatho says, “we have had a care to send… Constantine, a subdeacon of this holy spiritual mother, the Apostolic See, as well as Theodore, the presbyter legate of the holy Church of Ravenna…” Right there, the Apostolic See is called “spiritual mother”. The second time it comes up is when Agatho announces the Roman resources by which to prove dyotheletism: “To these same commissioners we also have given the witness of some of the holy Fathers whom this Apostolic Church of Christ receives, together with their books, so that, having obtained from the power of your most benign Christianity the privilege of suggesting, they might out of these endeavor to give satisfaction (when your imperial Meekness shall have so commanded) as to what this Apostolic Church of Christ, their spiritual mother and the mother of your God-sprung Empire, believes and preaches, not in words of worldly eloquence which are not at the command of ordinary men, but in the integrity of the apostolic faith, in which having been taught from the cradle, we pray that we may serve and obey the Lord of heaven, the Propagator of your Christian Empire, even unto the end. For a full treatment showing that Agatho meant the Roman Church, and the Roman Pontiff in particular, see Did Pope Agatho Teach Papal Infallibility in His Dogmatic Epistle Accepted by the 6th Ecumenical Council.
 An obvious reference to St. Peter and St. Paul’s founding of Rome.