An error held by some Catholics is that a pope cannot err, yet the Church has never taught such a thing. A pope indeed cannot profess or declare magisterial something that is a manifest error, but a pope can make slight, inadvertent mistakes or allow slight errors to creep into his speech. After all, popes are only human, they’re not infallible.
For instance, Pope Paul VI initially declared Vatican II to be the work of God, which he believed in the innocence of his heart, but he later recanted this by saying that Vatican II was the fissure through which Satan entered the Church (June 29, 1972). After 1970 Pope Paul had nothing good to say about Vatican II but rather lamented it.
Consider too that Pope John Paul II allowed the errant practice of receiving Communion in the hand, but deep down he disagreed with it even saying at one point:
“I don’t want this practice.” (Fulda, Germany, November 1980)
Slight mistakes committed by popes do not contradict the Church’s teaching on Papal Infallibility. When it is taught that a pope cannot profess heresy in his writings or speeches it simply means that this profession cannot officially be made and completed while he is pope, for upon attempting to profess heresy he automatically loses his papacy and is reduced to a heretic, whereby the profession is made as a heretic and not as a pope.
For instance, a pope could never deny the historicity of the Resurrection or profess that God works through other religions and remain pope since these would be professions of heresy. Consider the words of St. Alphonsus Liguori (1696-1797), Doctor of the Church:
“If ever a pope, as a private person, should fall into heresy, he should at once fall from the Pontificate. If, however, God were to permit a pope to become a notorious and contumacious heretic, he would by such fact cease to be pope, and the apostolic chair would be vacant.”
An example of a notorious heretic would be one that formally dignifies other religions. Some might ask, “Are you saying that God doesn’t bless members of other religions?” Answer: God indeed can bless individual members of other religions, but the primary reason for blessing them is to deliver them from these religions since God neither abides in other religions nor does he engender their activities.
The Church dogmatically teaches:
There is one holy Catholic and Apostolic Church, outside of which there is neither salvation nor remission of sins.
— Unam Sanctam, Papal Bull of Boniface VIII
Hence any pope who denies this dogma or who encourages the faithful to cast it aside in favor of ecumenism immediately ceases to be pope. A formal declaration that Catholics may join or merge with other religions would breach this dogma.
The same applies for a pope who contravenes any doctrine of the Faith, be it ordinary or extraordinary. This teaching is held not by a few but by all the ancient fathers of the Church.
St. Robert Bellarmine, Doctor of the Church, makes it clear:
“A Pope who is a manifest heretic automatically ceases to be a Pope and head, just as he ceases automatically to be a Christian and member of the Church. Wherefore, he can be judged and punished by the Church. This is the teaching of all the ancient Fathers who teach that manifest heretics immediately lose all jurisdiction.”
St. Francis de Sales echoes this point as well:
“Now when the Pope is explicitly a heretic, he falls ipso facto from his dignity and out of the Church…”
The 1913 Catholic Encyclopedia states:
“The Pope himself, if notoriously guilty of heresy, would cease to be pope because he would cease to be a member of the Church.”
St. Antoninus says that such a pope who is cut off from the Mystical Body cannot be the head of that Body.
“In the case in which the Pope would become a heretic, he would find himself, by that very fact alone and without any other sentence, separated from the Church. A head separated from a body cannot, as long as it remains separated, be head of the same body from which it was cut off.”
The lus Canonicum on the 1917 Code of Canon Law by Wernz-Vidal makes this same point:
“A pope who falls into public heresy would cease ipso facto to be a member of the Church; therefore, he would also cease to be head of the Church.” It adds, “A doubtful pope is not pope.”
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