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Papal Infallibility

Apostolic Apologetics: Papal Infallibility


Papal infallibility is by no measure the most understood of topics relating to Catholicism, to the contrary, it is one of the most misrepresented dogmas of Catholic theology. This document will give an examination of the official Catholic teaching regarding Papal infallibility. I will also attempt to answer common objections.

"…The pope is not an oracle, he is infallible on the rarest of occasions, as we know…" -Pope Benedict XVI

Quick Facts

Papal infallibility applies to the Pope only under strict circumstances. These will be explained below. First some things you should know:

  • This doctrine was defined dogmatically in the First Vatican Council of 1870. See below for the Canon.
  • Since it's definition in 1870, Papal infallibility has been used once--in 1950, by Pope Pius XII defining the assumption of Mary.
  • Infallibility must be carefully distinguished both from Inspiration and from Revelation.
  • In practice, Popes rarely use "Papal Infallibility".
  • No Ex Cathedra definition of any Pope has ever been shown to be erroneous.
  • Papal infallibility does not mean the Pope is impeccable (sinless).
  • Pope Benedict XVI confesses his sins once a week.

The Declaration

As is the case with essentially all officially declared doctrine, not until a teaching is questioned (usually within the Church itself) is there an official decree made. The Catholic Church holds that the Sacred Tradition of the Catholic Church, from the earliest centuries of it's existence, testifies to the Infallibility of Pope, when speaking under the criteria set forth below, both in this declaration and the following outline (criteria for infallibility). I will elaborate on the examples and exposition of the father regarding both Petrine Primacy, and the function of speaking Ex Cathedra in another article, as they move into other subjects not confined within this scope.

See the full English text by clicking here.

Vatican Council, Sess. IV , Const. de Ecclesiâ Christi, Chapter IV


And so We, adhering faithfully to the tradition received from the beginning of the Christian faith, to the glory of God, our Savior, the elevation of the Catholic religion and the salvation of Christian peoples, with the approbation of the sacred Council, teach and explain that the dogma has been divinely revealed: that the Roman Pontiff, when he speaks ex cathedra, that is, when carrying out the duty of the pastor and teacher of all Christians by virtue of his supreme apostolic authority he defines a doctrine of faith or morals to be held by the universal Church, through the divine assistance promised him in blessed Peter, operates with that infallibility with which the divine Redeemer wished that His church be instructed in defining doctrine on faith and morals; and so such definitions of the Roman Pontiff from himself, but not from the consensus of the Church, are unalterable.

(Canon). But if anyone presumes to contradict this definition of Ours, which may God forbid: let him be anathema.


Itaque Nos traditioni a fidei christianae exordio perceptae fideliter inhaerendo, ad Dei Salvatoris nostri gloriam, religionis catholicae exaltationem et christianorum populorum salutem, sacro approbante Concilio, docemus et divinitus revelatum dogma esse definimus: Romanum Pontificem, cum ex cathedra loquitur, id est, cum omnium Christianorum pastoris et doctoris munere fungens pro suprema sua Apostolica auctoritate doctrinam de fide vel moribus ab universa Ecclesia tenendam definit, per assistentiam divinam ipsi in beato Petro promissam, ea infallibilitate pollere, qua divinus Redemptor Ecclesiam suam in definienda doctrina de fide vel moribus instructam esse voluit; ideoque eiusmodi Romani Pontificis definitiones ex sese, non autem ex consensu Ecclesiae, irreformabiles esse.

(Canon.) Si quis autem huic Nostrae definitioni contradicere, quod Deus avertat, praesumpserit : anathema sit.

  Criteria for Infallibility

  1. The Pope must speak Ex Cathedra (from the Chair of Peter) in his official capacity.
  2. The decision must be binding on the whole Church.
  3. It must be on a matter of faith or morals.
  4. He must be intending to teach.


In most cases, the rejection of Papal infallibility stems from a misunderstanding of the teaching of the Catholic Church on this matter, though not always. Below I will try to address some common arguments.

Peter corrected by Paul

Q: Didn't Paul correct Peter? Doesn't this prove infallibility false?

Galatians 2:11

But when Cephas came to Antioch I opposed him to his face, because he stood condemned.

A: Argumentum stramineus homo, that is, a straw man argument [ W ]. Again, the doctrine of Papal Infallibility says nothing to the effect that Popes are "always mistake free". It is indeed a fact that most of the official objections to Papal infallibility set forth by non-Catholic Churches cite the remaining ability of the Pope to sin.

St. Peter was guilty of a venial fault of imprudence. In the mean time, no Catholic denies but that the head of the Church may be guilty even of great sins. What we have to admire, is the humility of St. Peter on this occasion, as St. Cyprian observes, who took the reprehension so mildly, without alleging the primacy, which our Lord had given him. Baronius held that St. Peter did not sin at all, which may be true, if we look upon his intention only, which was to give no offense to the Jewish converts; but if we examine the fact, he can scarce be excused from a venial indiscretion. (Witham)

Tertullian and most interpreters take notice, that St. Peter's fault was only a lesser or venial sin in his conduct and conversation. Did not St. Paul on several occasions do the like, as what is here laid to St. Peter's charge? That is, practice the Jewish ceremonies: did not he circumcise Timothy after this, an. 52 [in the year A.D. 52]? did he not shave his head in Cenchrea, an. 54? did he not by the advice of St. James (an. 58.) purify himself with the Jews in the temple, not to offend them?

What Paul accuses Peter of, Paul does himself afterwards.

Galatians 2:14 But when I saw that they walked not uprightly unto the truth of the gospel, I said to Cephas before them all: If thou, being a Jew, livest after the manner of the Gentiles and not as the Jews do, how dost thou compel the Gentiles to live as do the Jews?

Commentary (Haydock)

Did not St. Paul on several occasions do the like, as what is here laid to St. Peter's charge? that is, practise the Jewish ceremonies: did not he circumcise Timothy after this, an. 52 [in the year A.D. 52]? did he not shave his head in Cenchrea, an. 54? did he not by the advice of St. James (an. 58.) purify himself with the Jews in the temple, not to offend them?

Acts 16:3
Him Paul would have to go along with him: and taking him, he circumcised him, because of the Jews who were in those places. For they all knew that his father was a Gentile.

The Biblical Infallibility of Peter

Q: Is there a single instance of Peter demonstrating infallibility in the Bible?

A: I'm not going to (in this article) lay out the examples of Petrine Primacy, though it must also acknowledge that Peter did have some kind of infallibility—it cannot be denied that he wrote two infallible epistles of the New Testament while under protection against writing error. So, if his behavior at Antioch was not incompatible with this kind of infallibility, neither is bad behavior contrary to papal infallibility in general.

What infallibility does do is prevent a pope from solemnly and formally teaching as "truth" something that is, in fact, error. It does not help him know what is true, nor does it "inspire" him to teach what is true. He has to learn the truth the way we all do—through study—though, to be sure, he has certain advantages because of his position.

Popes disagreed with other Popes

Q: Sometimes Popes disagreed with other Popes. Doesn't this prove the doctrine false?

This, too, shows an inaccurate understanding of infallibility, which applies only to solemn, official teachings on faith and morals, not to disciplinary decisions or even to unofficial comments on faith and morals. A Pope’s private theological opinions are not infallible, only what he solemnly defines is considered to be infallible teaching.

Galileo Galilei

Q: Doesn't the case of Galileo, having been condemned, then later rehabilitated prove the doctrine false?

A: Pope Urban VIII never engaged papal infallibility. Galileo's work was handed condemnation through tribunal, not the Pope, though the Pope ratified the verdict, he at no time approached the criteria for Infallibility, nor was there even an attempt.

Related Links

  1. Catholic Answers: Papal Infallibility
  2. Catholic Bridge: The Pope (infallibility)
  3. Biblical Catholic Apologetics: Papal Infallibility
  4. Wikipedia: Papal Infallibility
  5. New Advent: Infallibility
  6. Original Catholic Encyclopedia: Infallibility
  7. See Also: Peter the Rock (local article)