Can the Pope Be Wrong?

Before any particular case, the principle must be stated: the pope's fallibility is not a concession wrung from the Church by her enemies; it is something the Church herself teaches. The Catechism, in defining infallibility, immediately draws its limits: the charism operates only "when [the pope] proclaims by a definitive act a point of doctrine concerning faith or morals"^[1]. Everything else — the immense majority of what a pope says and does — is not covered.

What the Catholic faith never claimed

Three confusions keep recurring. Clearing them away is enough to dispel the false scandal.

First, infallibility is not impeccability. The two words sound alike but are unrelated: impeccability concerns holiness of life, infallibility the truth of teaching. A pope can be a poor Christian without the deposit of faith he transmits being affected. Vatican I knew this perfectly well when proclaiming the dogma: history already counted saintly popes and scandalous popes.

Second, infallibility is not inspiration. The pope is not a prophet: he receives no revelations, does not complete the Gospel, and adds nothing to Revelation, closed at the death of the last apostle. Pastor Aeternus says so explicitly — the Spirit was not promised to Peter's successors "so that they might make known new doctrine by his revelation", but so that they might "holily guard and faithfully expound" the deposit received^[2].

Finally, infallibility is not omniscience. On economics, the climate, history, medicine or politics, a pope's opinion is worth only what his real competence is worth — and he can be mistaken like any educated man. The charism bears only on "faith and morals"^[3], that is, on what God revealed for our salvation.

"The Roman Pontiff […] enjoys this infallibility […] when, as supreme pastor and teacher of all the faithful, he proclaims by a definitive act a point of doctrine concerning faith or morals." — Second Vatican Council, Lumen Gentium, no. 25 (1964)^[4]

The formula is restrictive by construction: it states when the pope is protected by this personal charism — and thus, by implication, that outside this case he remains fallible. With one crucial reservation: the pope also shares in the infallibility of the ordinary and universal magisterium when, in union with the bishops of the whole world, he definitively proposes a truth to be held (see below), and he teaches infallible doctrine whenever he reaffirms a truth already defined, without laying down a new definition.

The proof given by the Gospel itself: Peter corrected by Paul

The finest argument for the pope's fallibility comes not from the Church's enemies, but from Sacred Scripture. The first pope, Saint Peter, was publicly corrected by Saint Paul at Antioch. For fear of the Jewish Christians come from Jerusalem, Peter had stopped sharing the table of converts of pagan origin, thus giving an example of duplicity contrary to the truth of the Gospel. Paul does not stay silent:

"But when Cephas came to Antioch I opposed him to his face, because he stood condemned. […] But when I saw that they were not straightforward about the truth of the gospel, I said to Cephas before them all, 'If you, though a Jew, live like a Gentile and not like a Jew, how can you compel the Gentiles to live like Jews?'" — Saint Paul, Epistle to the Galatians 2:11-14^[5]

Saint Augustine, against Saint Jerome who wanted to soften the scene, maintains that it must be taken literally: Peter really erred in his conduct, and Paul really corrected him^[6]. Peter himself, far from rebelling, gives an example of humility by accepting the rebuke — which tradition remembers as a summit of his holiness. The lesson is crystal clear: from the very first pope, the Church knows that Peter's successor can fail in his conduct and even in his practical judgment, without this taking anything away from the charge received from Christ to "strengthen your brethren" in the faith (Lk 22:32). The episode of Peter denying Christ three times on the night of the Passion (Mt 26:69-75) says the same thing, more forcefully still.

To measure the extent of fallibility, we must first map the protected core — tiny — and then observe that all the surrounding territory remains exposed to error.

The protected core: the "ex cathedra" act

Infallibility attaches not to the person speaking, but to a precise act performed under precise conditions. Pastor Aeternus requires four conditions met at the same time: that the pope speak as supreme pastor of the whole Church, on a question of faith or morals, by a definitive act (ex cathedra), to bind the whole Church. If a single one is missing, we are no longer before an infallible act. The detail of these conditions is treated in What is papal infallibility?; here it suffices to retain their effect: this lock is so strict that, since the nineteenth century, there are only two definitions of this kind commanding unanimity — the Immaculate Conception (1854) and the Assumption (1950), both Marian^[7].

The Code of Canon Law adds a further guarantee, in the direction of prudence: "No doctrine is understood to be infallibly defined unless this is manifestly established."^[8] In other words, when in doubt, a text is presumed not to engage infallibility. Far from hovering over every word of the pope, the charism is the extremely rare exception, never the rule.

Everything else is fallible

Outside this core, the pope can err in very different registers. The table below contrasts the domains exposed to error with the single protected case.

One clarification is needed, lest we fall into the opposite excess: "non-infallible" does not mean "worthless" or "optional". The pope's ordinary magisterium — encyclicals, catecheses, exhortations — calls for a "religious respect of intellect and will", even when it defines no dogma^[9]. And when the ordinary and universal magisterium — the pope together with the bishops scattered throughout the world — proposes a doctrine "to be held definitively", it too becomes irreformable^[10]: "fallible" holds only for authentic but non-definitive teaching. Fallible here means non-definitive, hence in principle perfectible; this does not authorize treating the pope's current teaching lightly. The fine distinction between these degrees — dogma, definitive doctrine, authentic non-definitive teaching, opinion — is the subject of Doctrine, dogma and theological opinion.

Let us take up one by one, with examples, the terrains on which a pope has been able and can still be mistaken.

In his moral life: impeccability does not exist

No pope was ever held to be incapable of sinning. The most spectacular case is that of the Renaissance popes: Alexander VI Borgia (elected in 1492), father of several illegitimate children — Juan, Cesare, Lucrezia, Joffré — combining nepotism, simony and public scandals, remains the symbol of the carnal papacy of the late fifteenth century^[11]. And yet no serious Catholic theologian draws from Alexander VI's life an objection against infallibility, for a simple reason: the holiness of the man and the truth of the office are two distinct things. An immoral pope remains able to transmit the deposit of faith intact, exactly as a bad priest celebrates a valid Mass. The moral crisis of the papacy, treated in detail in The abuse crisis in the Church, was never a crisis of dogma.

"Infallibility does not make the pope incapable of sinning." — Constant principle of Catholic theology, already presupposed by Vatican I

In his private opinions and science: the Galileo affair

When a pope pronounces on a scientific question, he speaks as a man of his time — fallible. The Galileo affair is the best-known example. In 1633, the Florentine scholar was condemned as "vehemently suspected of heresy" for upholding the motion of the Earth. But this condemnation was the work of the Holy Office (the Roman congregation of the Inquisition), not a pontifical ex cathedra act: a decision of a Roman tribunal, even if approved by the pope, does not meet the conditions of the ex cathedra act (no solemn definition by the supreme pastor, no object of revealed faith, no address binding the universal Church)^[12]. Urban VIII, who had first protected Galileo, never solemnly defined, as supreme pastor of the whole Church, that the sun revolves around the Earth. The sentence belongs to discipline and scientific assessment, two domains explicitly outside the field of "faith and morals".

Saint John Paul II acknowledged in 1992, at the end of a study commission, that Galileo's judges had erred in unduly transposing a question of cosmology onto the terrain of the doctrine of the faith^[13]. This admission, far from weakening the dogma, illustrates its scope: the Church can acknowledge that one of her tribunals was mistaken, precisely because infallibility never covered that kind of decision.

In his government and prudence

The government of the Church is a matter of prudence, not dogma — and prudence can fail. Unhappy choices of collaborators, questionable appointments, mistaken diplomatic decisions, slowness or hastiness: the history of pontificates is full of them. None of these decisions falls under infallibility, which never bears on the conduct of affairs, but only on the definitive teaching of the faith. A pope could transfer the pontifical see to Avignon in the fourteenth century at the cost of a lasting weakening of the Church^[14], without any truth of faith being thereby wrongly defined. It is moreover on this terrain — government — that the saints sometimes addressed the pope their sharpest reproaches (see below, Saint Catherine of Siena).

In his non-definitive ordinary magisterium

There remains the most delicate case: the ordinary magisterium, that is, the pope's current teaching (encyclicals, exhortations, catecheses) when it lays down no definitive act. This teaching enjoys real authority and calls for the religious assent of the faithful^[15]; but, not being an irreformable definition, it remains in law perfectible. The Church has thus been able, over the centuries, to clarify, complete or develop points of non-definitive doctrine — for example on religious tolerance, lending at interest or the death penalty — without ever contradicting the defined dogmatic core. Distinguishing this ordinary magisterium from the ex cathedra act is exactly what makes it possible to understand how a pope can "be wrong" in non-definitive teaching without the Church ever being bound in error in an irreformable way.

Since Vatican I, the opponents of infallibility have never stopped brandishing a handful of historical cases. Far from hiding them, the Church examined them closely — and each time, they confirm the rule instead of breaking it: no pope ever defined an error ex cathedra. Here are the four most-cited dossiers, in chronological order.

Pope Liberius (352-366) and the formula of Sirmium

The classic first case. During the Arian crisis, Pope Liberius was exiled by Emperor Constantius II, who favored the Arians. After about two years of isolation at Beroea, in Thrace, and under threat, he is said to have signed, around 357, one of the formulas of Sirmium — an ambiguous text that omitted the decisive Nicene word (homoousios, "consubstantial") and condemned Saint Athanasius, the champion of orthodoxy^[16].

But examination destroys the objection. First, the very fact of the signature is historically disputed: our main sources (Athanasius, Hilary of Poitiers) are late, hostile, and some documents may be Arian forgeries. Second — and this is the decisive point — supposing Liberius did sign, he did so under duress, broken by exile and fear, in a private letter extorted by force: exactly the opposite of a free and solemn definition binding the whole Church. An act extorted by violence is neither free, nor magisterial, nor ex cathedra. Far from refuting infallibility, the Liberius case shows its conditions by default.

Pope Vigilius (537-555) and the Three Chapters quarrel

In the sixth century, Emperor Justinian wanted the "Three Chapters" (writings of three theologians suspected of Nestorianism) condemned, in order to rally the Monophysites. Pope Vigilius wavered spectacularly: he first refused, then yielded with his Iudicatum (548), retracted under pressure from the Western bishops, was dragged by force to Constantinople, condemned, recanted again, then finally approved the Second Council of Constantinople (553)^[17].

This ballet of hesitations is a textbook case of weak government — but in no way a defined error. Vigilius contradicted himself in successive, prudential and political acts, never in a solemn and constant dogmatic definition. On the contrary: orthodoxy finally triumphed through the council itself, recognized as ecumenical. The case illustrates that a pope can prevaricate, bend under imperial pressure, lack courage — without the truth of the faith ever being fixed backwards.

Pope Honorius I (625-638): condemned after his death

This is the most serious objection, the one the opponents of infallibility most exploited at Vatican I. Pope Honorius I, consulted by Patriarch Sergius of Constantinople on the question of Christ's wills, answered in two letters with an imprudent formula that seemed to favor Monothelitism (the heresy of a single will in Christ): "We confess one will of our Lord Jesus Christ." Nearly forty years after his death, the Third Council of Constantinople (681) anathematized Honorius by name, "who followed [the Monothelites] in everything", and Pope Leo II confirmed the sentence^[18].

The affair looks devastating; it is not, for three precise reasons. First, Honorius's letters are private correspondence with a patriarch, not an ex cathedra definition binding the whole Church: none of the four conditions is met. Second, read in context, Honorius's formula aims to rule out the idea of a conflict between Christ's human will and the divine will — an orthodox intention, clumsily expressed, and not the heretical affirmation of a single will in the Monothelite sense. Third, and decisively, Leo II expressly specifies the grounds of the condemnation: Honorius is blamed not for having taught heresy, but for having, through his negligence, "allowed the immaculate faith to be defiled"^[19].

"[Honorius], who did not illustrate this Apostolic See with the doctrine of the apostolic tradition, but attempted, by sacrilegious betrayal, to overthrow the immaculate faith." — Pope Leo II, letter confirming the council of 681^[20]

The nuance is crucial: Honorius is reproached with a culpable silence, a fault of government and vigilance, not an erroneous definition of the faith. Far from overturning infallibility, the case draws its exact boundary — a pope can fail gravely through negligence, without ever engaging the charism that operates only in the definitive act.

Pope John XXII (1316-1334) and the beatific vision

The clearest case of all, because it directly touches a question of faith. Between November 1331 and March 1332, Pope John XXII preached, in a series of sermons at Avignon, an erroneous thesis: in his view, the souls of the just would not enjoy the vision of God immediately after their death, but only after the Last Judgment^[21]. The thesis contradicted the common belief of the Church. The University of Paris condemned it; most of the theologians consulted opposed it; lively resistance rose throughout Christendom.

And it is here that the case becomes a demonstration of infallibility rather than a refutation. John XXII never imposed his thesis as a definition: he upheld it as a preacher's personal opinion, consulting, debating — and, on the eve of his death (he died on 4 December 1334), he retracted it, acknowledging that purified souls do see God face to face^[22]. Two years later, his successor Benedict XII solemnly settled the question in the constitution Benedictus Deus (29 January 1336) — that is an act of the definitive magisterium:

"We define that […] the souls [of the fully purified just] have seen and do see the divine essence with an intuitive vision and even face to face, without the mediation of any creature […] and will continue so without interruption until the Last Judgment, and thenceforth for eternity." — Benedict XII, constitution Benedictus Deus, 29 January 1336^[23]

The contrast is striking: a pope privately upholds an error, never defines it, retracts — and it is precisely the non-intervention of infallibility that left room for debate, resistance and correction. If John XXII could have defined the error ex cathedra, he would have done so: he did not. The protection worked exactly as the dogma announces — not by making the pope omniscient, but by preventing him from chaining the Church to a falsehood.

Four popes, four real weaknesses — and yet the dogma holds. Why? Because each of these cases, examined closely, falls outside the narrow field of infallibility.

The decisive distinction: person and office

Everything rests on a simple distinction: what is protected is not the pope's person, but the office he exercises in a given act. The person — the man Honorius, the man John XXII, the man Borgia — can sin, err, hesitate, preach false opinions. The office of supreme definer of the faith is protected only in the precise and rare instant in which he fully exercises it. The right image is not that of an oracle, but of a safeguard: God does not inspire the pope with what he must think; He merely prevents him from solemnly locking a falsehood in the name of the whole Church.

No error was ever defined "ex cathedra"

This is the massive fact that twenty centuries of history confirm: never has a pope defined ex cathedra a doctrine later recognized as false. Liberius signed a private letter under duress; Vigilius contradicted himself in political acts; Honorius sinned through negligence in correspondence; John XXII preached a personal opinion which he retracted. Not one of these errors took the form of a solemn, free definition on faith, for the whole Church. The record is without exception over two thousand years — which, for an institution governed by more than two hundred and sixty men, some of whom were mediocre or perverse^[24], is in itself a remarkable fact.

The rock holds despite the cracks

Christ's promise did not concern the perfection of men, but the indefectibility of the Church:

"You are Peter, and on this rock I will build my Church, and the powers of Hades shall not prevail against it." — Gospel according to Saint Matthew 16:18^[25]

This word never promised that Peter would be without sin or without error: it promised that the Church would not sink. The cracks in the rock — weak popes, sinful popes, popes erring in their opinions — never brought the edifice down. For the theologian, it is even an argument: had the Church depended on the virtue and learning of each pope, she would have disappeared twenty times over. That she crossed Borgia, Avignon and John XXII without ever defining a single heresy is, by contrast, the sign of an assistance that does not come from men.

There remains the practical, and often anguished, question: how should one react, as a believer, when the pope appears to be in error? Catholic tradition traces a narrow path between two cliffs.

Distinguishing the levels of authority

The first reflex is not to judge, but to discern the register. Has the pope just laid down an ex cathedra definition (an extremely rare case, and then the assent of faith is due), or expressed an opinion in an interview, a pastoral orientation, a decision of government? The immense majority of the time, it is the second case — and a non-definitive opinion can be discussed, nuanced, even respectfully contested on the theological plane. Confusing the two registers condemns one to anguish: a remark made on a plane is treated as a dogma, then everything collapses when the next pope says something else. The key is given by Doctrine, dogma and theological opinion.

The right and duty of respectful criticism

The history of the saints shows it: loving the pope does not forbid addressing him, where appropriate, with a filial correction. Saint Paul corrected Peter to his face (Gal 2:11). Saint Catherine of Siena, who called the pope "sweet Christ on earth" and owed him total obedience, nonetheless scolded Gregory XI with astonishing freedom, pressing him to leave Avignon, reform the Church and stop being afraid:

"Be a courageous man for me, and not fearful. […] Since God has given you authority and you have accepted it, use your virtue and your power." — Saint Catherine of Siena, Letter to Gregory XI (1376)^[26]

Saint Thomas Aquinas theorizes this possibility: there exists, he writes, a "fraternal correction" that can be addressed even to superiors, and an inferior may publicly resist a prelate "where there would be imminent danger to the faith", following Paul's example in correcting Peter^[27]. This correction is always made in respect, love and prayer — never in contempt or revolt. Its aim is to serve the pope, not to dethrone him.

Avoiding the two traps: papolatry and sedevacantism

Two symmetrical excesses lie in wait for the troubled believer.

The first is papolatry: making the pope an oracle whose every word falls from Heaven, to the point of turning the slightest interview into dogma. This is precisely the caricature that the four conditions of infallibility forbid. A believer who thinks "the pope is always right about everything" is preparing needless crises of faith for himself: a single unhappy phrase will suffice to shake his whole edifice.

The second, opposite trap is sedevacantism (and more broadly schismatic rigorism): concluding, from the fact that a pope errs or sins, that he is not truly pope, that the see is "vacant", and setting oneself up as judge of the Church in his place. This is the reverse slope, and equally false: it confuses fallible error (which never ceased to exist) with a break in the succession (which would destroy Christ's promise). None of the great historical cases — Honorius condemned, John XXII retracted — ever led the Church to declare the see vacant: the error was corrected within the Church, while remaining united to Peter's successor.

The Catholic way holds both ends: a lucid realism that knows the pope can fail, and a supernatural trust that knows the Church will not fail. That is exactly the balance of the dogma: modest about the man, firm about the promise. For the positive meaning of the Petrine ministry — why this successor of Peter is necessary despite everything — see Why the pope is necessary.

To the question "can the pope be wrong?", the Catholic answer is twofold and without evasion. Yes, about almost everything: his life, his opinions, science, government, his non-definitive teaching — and history proves it through Liberius, Vigilius, Honorius and John XXII. No, in the single solemn and extremely rare act in which he defines, as supreme pastor, a truth of faith for the whole Church — and history proves that too, since never, in two thousand years, did such an act fix an error.

This answer is no embarrassed retreat: it is the doctrine the Church herself teaches, from the Gospel where Paul corrects Peter to the Catechism that carefully bounds the charism. It frees the believer from two servitudes: the one that would make the pope a god, and the one that, faced with his weaknesses, would cast doubt on the Church. The pope is a fallible man serving a promise that does not fail.

• What is papal infallibility? — the simple definition of the charism, the four conditions of the ex cathedra act, and what infallibility is not.
• Papal Infallibility (1870) — the complete dossier: history of Vatican I, biblical and patristic foundations, detailed refutation of the objections (including Honorius in depth).
• Why the pope is necessary — the meaning of the Petrine ministry and of Peter's primacy.
• Doctrine, dogma and theological opinion — the degrees of authority in the Church's teaching, indispensable for distinguishing the registers of papal speech.
• The abuse crisis in the Church — the moral crisis of the papacy and clergy, from the Borgias to today, and the Church's response.
• Apostolic succession — how Peter's authority passes from pope to pope.