The doctrine of conciliar infallibility is the belief that the Church’s Ecumenical Councils are, through the guidance of the Holy Spirit, completely without dogmatic error. In this article, I hope to demonstrate that this has been the normative and universal belief of the Church from her earliest days, until today.

Given the first Ecumenical Council didn’t happen until the 4th century, it’s not surprising that it’s around this time that we begin to see the Fathers commenting on the authority of these Councils. Interestingly, one of the first witnesses we have to these Councils being “divinely inspired” in some sense is from the man who called I Nicaea. In his Letter to the Churches, Emperor St. Constantine referred to the decisions of the Nicene Council as “divine commands,” and stated that, “whatever is done in the sacred assemblies of the bishops is referable to the divine will.” Although it’s not an explicit affirmation of conciliar infallibility, Constantine nevertheless sees something uniquely “divine” about conciliar definitions.  

Unfortunately, the acts of the Nicene Council have been lost to history, and so it’s not easy to say how the Council Fathers viewed their own authority. However, in addition to the witness of Constantine, we have the writings of another important figure who was at the Council, namely St. Athanasius the Great. Athanasius wrote an entire work On Councils that discussed this matter in detail. He writes that “divine providence” saw to it that the Council of Nicaea would “exhibit the faith without guile or corruption” (1:2). He says that it “was not a common meeting” but rather “an Ecumenical Council,” which is why it had the ability to anathematize Arianism (1:5). And importantly, Athanasius states that the Councils’ teachings can be used alongside Scripture to determine the true faith (1:6). 

Once again, perhaps you can argue that Constantine and Athanasius were too vague to be considered conciliar infallibilists, however you cannot deny that they believed there was something akin to “divine inspiration” going on at the First Ecumenical Council. 

And this sentiment was also shared by one of Athanasius’ theological successors, St. Basil the Great. In his Letter to Cyriacus, Basil tells Cyriacus that he “should confess the faith put forth by our Fathers once assembled at Nicaea [and] not omit any one of its propositions,” because this Council “did not speak without the operation of the Holy Spirit.” Notice how Basil doesn’t say that you must follow I Nicaea because its teachings are correct (though he obviously believed they were), but rather because it was guided by the Spirit. In other words, there’s something “divine” about the Council that makes it authoritatively binding in and of itself. 

St. Augustine of Hippo, a contemporary of Basil, explained this subject in more detail during the Donatist controversy. In an attempt to justify their position on re-baptizing schismatics and heretics, the Donatists appealed to the witness of St. Cyprian; and in response to this, Augustine explains how his own view of sacramental validity is supported by, “the unanimous authority of the whole Church, to which he [Cyprian] himself would unquestionably have yielded, if at that time the truth of this question had been placed beyond dispute by the investigation and decree of a plenary Council” (Against the Donatists, 2:4). 

Augustine affirms that, if Cyprian had been alive when a “plenary Council” condemned his views, he would have “unquestionably yielded” to that decision, because the “unanimous authority of the whole Church” would have settled the matter “beyond dispute.” This tells us that, for Augustine, plenary Councils are authoritative in their own right; and once they make a decision, you have an obligation to align your views with that decision, because it’s “unquestionable.” Notice how this is not only an explicit affirmation of conciliar infallibility, but it’s also fundamental to the Saint’s apologetic against heretics: true Christians yield their theology to the authority of Church Councils, and heretics do not. We do not judge the Councils, rather we allow the Councils to judge us.

Few Saints in antiquity expressed this more than St. Vincent of Lerins. In his famous Commonitorium, Vincent goes into great detail explaining how we can discern “the faith once delivered to the Saints”; and fundamental to this process is the witness of Ecumenical Councils. He states quite matter-of-factly that “by the decree and authority of a Council, the rule of the Church’s faith may be settled” (28:75). He teaches that “those who would keep clear of heresy… should ascertain whether any decision has been given in ancient times as to the matter in question by the whole priesthood of the Catholic Church, with the authority of a General Council” (29:77). And Vincent takes his own advice. 

When explaining how we should discern the true faith, Vincent is clear that he’s not just making stuff up, but “lest we should seem to allege presumptuously on our own warrant rather than on the authority of the Church, we appealed to the example of the holy Council which some three years ago was held at Ephesus in Asia.” He explains how the Third Ecumenical Council used the Commonitorium’s method of discerning the apostolic faith (i.e. they “cleaved to antiquity” by analyzing the writings of the Fathers), after which they gave a “consistent and unanimous judgment” that “established the rule of divine truth” (29:78). As far as Vincent was concerned, the “Vincentian canon” isn’t his own opinion, but rather the Church’s authoritative teaching, because it was employed at an Ecumenical Council. This means that Vincent didn’t simply equate “the authority of the Church” with official decrees from the Councils, but also their very proceedings/acts. This is what we must submit to in order to have a “right understanding of the prophets and apostles… in accordance with the standard of Ecclesiastical and Catholic interpretation” (2:5). 

Clearly, St. Vincent had a very high view of conciliar infallibility, perhaps even falling into what Fr. Richard Price refers to as “conciliar fundamentalism.” This is a term that Fr. Price came up with to describe the backdrop of the Fifth Ecumenical Council. To make a long story short, II Constantinople was called to address an issue that had come up at the Fourth Ecumenical Council of Chalcedon. The question was whether or not sessions nine and ten of Chalcedon wrongfully rehabilitated three former Nestorians (hence this was called the “Three Chapters” controversy). Because this was making a potential union with the Monophysites much more difficult, there were some who just wanted to throw these sessions of Chalcedon under the bus, however the Church would have none of this. In the time leading up to the Fifth Council, Ferrandus of Carthage (a companion of St. Fulgentius of Ruspe) wrote:

If there is disapproval of any part of the Council of Chalcedon, the approval of the whole is in danger of becoming disapproval… But the whole Council of Chalcedon, since the whole of it is the Council of Chalcedon, is true; no part of it is open to criticism. Whatever we know to have been uttered, transacted, decreed and confirmed there was worked by the ineffable and secret power of the Holy Spirit. (Quoted from Fr. Richard Price, “The Acts of the Council of Constantinople of 553”)

According to Fr. Price, Ferrandus’ view of complete conciliar infallibility, which extends not only to official decrees but also the conciliar acts, was shared by Emperor St. Justinian, and was one of the very reasons why he called the Fifth Council. Indeed, as Craig Truglia notes, “the Three Chapters controversy would not have been a controversy if the fathers had the epistemic ‘out’ of simply saying that Sessions 9 and 10 of Chalcedon were not decrees and canons.” In other words, if absolute conciliar infallibility wasn’t the normative belief of the Church, then II Constantinople would have essentially been pointless. 

Understanding this provides an important context to the Fifth Council’s view of its own authority. Not only does it go to extreme lengths to defend itself against the charge of abrogating Chalcedon, but the conciliar Fathers make strong arguments in favor of their own infallible authority. When the Council deposed Pope Vigilius for refusing to condemn the Three Chapters, they explicitly appealed to Acts 15:28, “it has seemed good to the Holy Spirit and to us,” and Matthew 18:18-20, “if two of you shall agree upon earth… they shall have it from my Father,” to describe their conciliar authority, saying that “there is no other way in which truth can be made manifest” except through Church Councils (The Sentence of the Synod). 

It’s worth noting that, one century earlier, these same passages were appealed to by Pope St. Celestine in his Letter to the Synod of Ephesus, to explain what they were going to do at the Third Ecumenical Council. And not too long after the Fifth Council, Pope St. Gregory would also use passages from Matthew 16-18 to describe why “I receive and revere, as the four books of the Gospel so also the four Councils… [and] the fifth Council also I equally venerate” (Book I, Letter XXV). Far from being an outlier, treating the Ecumenical Councils as borderline “divinely inspired” seems to have been the norm. And this was never viewed as some kind of “later development,” but rather this infallible authority has always been seen as a gift from Jesus Christ Himself.

From here, conciliar claims to infallibility would only get more explicit. At the Sixth Ecumenical Council, the Fathers wrote a letter to Pope St. Agatho stating that they “have put forth, by the assistance of the life-giving Spirit, a definition, clean from all error, certain, and infallible” (Letter of the Council to St. Agatho). And in this definition that the Council Fathers are referring to, they call the Fathers of previous Councils “God-inspired,” and they say of themselves, “this our holy and Ecumenical Synod inspired of God.” Although claims of divine inspiration can sometimes be exaggerated (as when imperial edicts are referred to this way), the broader context of the Council definitely lends itself to a more literal interpretation of these words. 

[Contrast this with the view of Reformed theologian Francis Turretin, “all joined together in a council, [the Church] is not infallible, but is liable to deadly error as well in faith as in practice, in questions of right as well as in questions of fact” (Institutes of Elenctic Theology, p. 72). It’s night and day.]

Moreover, about a century later, the Church would be forced to further articulate her understanding of conciliar infallibility because of the iconoclast controversy. In 754, the Byzantine Emperor summoned the (robber) Council of Hieria to condemn the veneration of holy icons. Because this iconoclast Council claimed ecumenical and infallible authority for itself, the Seventh Ecumenical Council (which was called to respond to the robber Synod) had to explain why Hieria wasn’t actually authoritative. In its sixth session, II Nicaea ruled the following:

And how can a council be ‘great and ecumenical’ when it received neither recognition nor assent from the primates of the other churches, but they consigned it to anathema? It did not enjoy the cooperation of the then pope of Rome or his priests, neither by means of his representatives or an encyclical letter, as is the rule for councils; nor did it win the assent of the patriarchs of the east, of Alexandria, Antioch, and the holy city, or of their priests and bishops. (Quoted from UbiPetrus, “What Makes a Council Ecumenical?”)

The Seventh Council explains that Hieria cannot be infallible because it lacked approval from the Apostolic Sees of Rome, Alexandria, and Antioch (among others). Obviously, if conciliar infallibility wasn’t the belief of the Church, then the Seventh Council could have simply stated as much. They could have just said that “Councils aren’t infallible,” and thus there’s no reason to listen to Hieria. However, instead of rejecting conciliar infallibility, II Nicaea simply explained why it doesn’t apply to robber Synods. Indeed, this apologetic would become fundamental to the defenders of the Seventh Council’s legacy.  

St. Nikephoros of Constantinople, a zealous 9th century advocate for icon veneration, followed II Nicaea in arguing that any controversies that arise in the Church, “are resolved and defined by the Ecumenical Synods, with the assent and approbation of the bishops who hold the Apostolic Sees” (Ibid). Likewise St. Theodore the Studite, an iconodulistic contemporary of Nikephoros, wrote that “divine and heavenly decisions” are reserved for “the successors of the Apostles,” who are the Patriarchs of Rome, Constantinople, Alexandria, Antioch, and Jerusalem. Theodore states, “That is the Pentarchic authority in the Church. It is to them that all decision belongs in divine dogmas” (Ibid). Once again, conciliar infallibility is never contested by anyone in the ancient Church, instead its precise conditions are articulated and defended more clearly as the doctrine becomes more central to ecclesial controversies.

A few centuries later, this issue of conciliar infallibility would come up again at the Council of Constantinople +1351. At this Council, the defenders of St. Gregory Palamas brought forward the acts of the Sixth Council to argue for the essence energy distinction, however, “the dissenters at once cried out, ‘Not the Acts of the council, but read the definition only.’” This “divine Synod” didn’t understand why Palamas’ opponents refused to accept the acts of III Constantinople as infallible, calling their opinion “futile and evil” because it “[did] not at all accepting the reading of the Acts” (The 1351 Synod of Constantinople, par. 12). Notice once again that the Church not only affirms the infallibility of the Ecumenical Councils’ decrees, but also their proceedings/acts; and this is never something the Church needs to defend, rather it’s always just been assumed.

Not too long after this, the precise conditions of conciliar infallibility (not its fact) would come up again because of the robber Council of Florence, which “dogmatically” taught the heresies of papal indefectibility, and the Filioque. Like the iconoclast Council of Hieria, Florence claimed to be ecumenical and thus infallibly binding. Indeed to this day, there are some (uninformed) Roman Catholics who try to argue this point against Holy Orthodoxy. However, as St. Gennadius Scholarius wrote in his Apologia Against the Union, Florence was not approved by the Apostolic See of Alexandria (represented by St. Mark of Ephesus), which ipso facto excludes it from II Nicaea’s definition of an infallible Council; and the representatives of the other Sees who did approve of Florence, were not only directly disobeying their Patriarchs (thus being unable to speak on their behalf), but they were also renounced by them upon return (p. 37-38). As always, conciliar infallibility is never brought into question, but only its conditions are commented on.

Indeed, in his discussion of this same topic, St. Nikodemus the Hagiorite explains that Ecumenical Councils “must be unanimously accepted by all the Patriarchs and hierarchs of the Catholic Church,” and if this happens, then these Councils possess “infallibility… [because] the decisions of the Ecumenical Councils are equivalent to the decisions of the Holy Spirit of truth” (The Rudder). However, Nikodemus further explains the conditions for this infallibility by stating that Patriarchal ratification doesn’t have to be instantaneous. He lists the Councils of Carthage +419 and Trullo +692 as examples of local Synods that later received ecumnical authority. 

Likewise, St. Nikodim Milaš teaches that “when everyone agrees on a well-known decision [of a local Synod], then it is announced in the name of the Church, and it receives the same significance and force as the decision of an Ecumenical Council” (Orthodox Church Law). Nikodim lists the 1642 Confession of St. Peter Mogila as an example of this, documenting how “this confession was approved, first of all, at one Kiev Council, then at the Iasi Council, and then it was revised and approved by all four Eastern Patriarchs and unanimously accepted by the entire Orthodox Church. Thus… [it] has the same importance and significance as if it had been compiled by an Ecumenical Council.” And just a few years ago, the Synod of Crete +2016 essentially reiterated this same point:

The Orthodox Church, in her unity and catholicity, is the Church of Councils, from the Apostolic Council in Jerusalem (Acts 15.5-29) to the present day. The Church in herself is a Council, established by Christ and guided by the Holy Spirit, in accord with the apostolic words: “It seemed good to the Holy Spirit and to us” (Acts 15.28). Through the Ecumenical and Local councils, the Church has proclaimed and continues to proclaim the mystery of the Holy Trinity, revealed through the incarnation of the Son and Word of God. The Conciliar work continues uninterrupted in history through the later councils of universal authority [e.g. the Councils of 879, 1341, 1351, 1368, 1484, 1642, 1672, and 1872]. (Encyclical of the Holy and Great Council of the Orthodox Church, I.3)

In conclusion, from everything that’s been discussed above, it should be clear that conciliar infallibility has always been the Church’s belief. From the days of Ss. Basil, Augustine, and Vincent, to Ss. Scholarius, Nikodemus, and Nikodim, Orthodoxy has always professed that the rulings of Ecumenical Councils are “clean from all error, certain, and infallible.” The fact that most Protestant denominations today reject this belief, is one of the chief signs of their departure from historic Christianity. Thanks for reading!