Objection 18): The Council of Constance condemned the idea that a heretic would cease to be the pope.

Errors of John Hus, Condemned by the Council of Constance: “#20. If the Pope is wicked and especially if he is foreknown (as a reprobate), then as Judas, the Apostle, he is of the devil, a thief, and a son of perdition, and he is not the head of the holy militant Church, since he is not a member of it."[1] – Condemned

Answer: No, the Council of Constance didn’t condemn the idea that a heretic would cease to be the pope at all.  This is a serious misunderstanding of this proposition.  As we see clearly above, the Council condemned something significantly different.  It condemned the proposition that a wicked man would cease to be the head of the Church, since he is not a member of it.  The proposition from the heretic Hus rightly asserts that one who is not a member of the Church cannot be the head of the Church, but it falls into trouble by stating that the pope ceases to be a member if he is “wicked.”

Pope Pius XII, Mystici Corporis Christi (# 23), June 29, 1943:
“For not every sin, however grave it may be, is such as of its own nature to sever a man from the Body of the Church, as does schism or heresy or apostasy.”[2]

A merely wicked pope doesn’t cease to be pope, but a heretic or schismatic does.  This is because heresy and schism and apostasy separate one from the Church, while other sins (no matter how grave or wicked they are) do not.  Thus, we can see clearly that the proposition is condemning the idea that wickedness separates one from the Church.  It is not condemning the truth that a heretic ceases to be the pope.  In fact, many of the other propositions from John Hus which were condemned by the Council of Constance repeat the false idea expressed above in different ways: that the wicked are not part of the Church.[3]

St. Robert Bellarmine, De Romano Pontifice, Book II, Chap. 30:
"This principle is most certain.  The non-Christian cannot in any way be pope, as Cajetan himself admits (ib. c. 26).  The reason for this is that he cannot be head of what he is not a member; now he who is not a Christian is not a member of the Church, and a manifest heretic is not a Christian, as is clearly taught by St. Cyprian (lib. 4, epist. 2), St. Athanasius (Scr. 2 cont. Arian.), St. Augustine (lib. De great. Christ. Cap. 20), St. Jerome (contra Lucifer.) and others; therefore the manifest heretic cannot be pope.”

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