St. Robert Bellarmine (1610), Doctor of the Church: "A pope who is a manifest heretic
automatically (per se) ceases to be pope and head, just as he ceases automatically to be a
Christian and a 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, Doctor of the Church:
“It would indeed be one of the strangest monsters that could be seen – if the head of
the Church were not of the Church.”
Pope Paul IV, Bull Cum ex Apostolatus Officio, Feb. 15, 1559: “6. In addition, [by this Our
Constitution, which is to remain valid in perpetuity, We enact, determine, decree and
define:] that if ever at any time it shall appear that any Bishop, even if he be acting as an
Archbishop, Patriarch or Primate; or any Cardinal of the aforesaid Roman Church, or, as
has already been mentioned, any legate, or even the Roman Pontiff, prior to his
promotion or his elevation as Cardinal or Roman Pontiff, has deviated from the
Catholic Faith or fallen into some heresy:
(i) the promotion or elevation, even if it shall have been uncontested and by the
unanimous assent of all the Cardinals, shall be null, void and worthless;
(ii) it shall not be possible for it to acquire validity (nor for it to be said that it has thus
acquired validity) through the acceptance of the office, of consecration, of subsequent
authority, nor through possession of administration, nor through the putative
enthronement of a Roman Pontiff, or Veneration, or obedience accorded to such by all,
nor through the lapse of any period of time in the foregoing situation;
(iii) it shall not be held as partially legitimate in any way…
(vi) those thus promoted or elevated shall be deprived automatically, and without need
for any further declaration, of all dignity, position, honour, title, authority, office and
power…