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None of those men take a disrespectful and hostile attitude toward the Pope. And the last example is fallacious because St. Paul was rebuking another man named Peter, not St. Peter.

(not that you're honest enough to watch it)

And you accuse me of "private judgment" in interpreting Scripture? 

Haydock Bible Commentary on Galatians 2:11

Ver. 11. But when Cephas, &c.[1] In most Greek copies, we read Petrus, both here and ver. 13. Nor are there any sufficient, nor even probable grounds to judge, that Cephas here mentioned was different from Peter, the prince of the apostles, as one or two later authors would make us believe. Among those who fancied Cephas different from Peter, not one can be named in the first ages[centuries], except Clemens of Alexandria, whose works were rejected as apocryphal by Pope Gelasius. The next author is Dorotheus of Tyre, in his Catalogue of the seventy-two disciples, in the fourth or fifth age[century], and after him the like, or same catalogue, in the seventh age[century], in the Chronicle, called of Alexandria, neither of which are of any authority with the learned, so many evident faults and falsehoods being found in both. St. Jerome indeed on this place says, there were some (though he does not think fit to name them) who were of that opinion; but at the same time St. Jerome ridicules and rejects it as groundless. Now as to authors that make Cephas the same with St. Peter, the prince of the apostles, we have what may be called the unexceptionable and unanimous consent of the ancient fathers and doctors of the Catholic Church, as of Tertullian, who calls this management of St. Peter, a fault of conversation, not of preaching or doctrine. Of St. Cyprian, of Origen, of the great doctors, St. Jerome, St. Augustine, St. Chrysostom, St. Gregory the Great, of St. Cyril of Alexandria, of Theodoret, Pope Gelasius, Pelagius the second, St. Anselm, St. Thomas Aquinas. In later ages, of Bellarmine, Baronius, Binius, Spondan, of Salmeron, Estius, Gagneius, Tirinus, Menochius, Alex Natalis, and a great many more: so that Cornelius a Lapide on this place says, that the Church neither knows, nor celebrates any other Cephas but St. Peter. 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, practise the Jєωιѕн ceremonies: did not he circuмcise Timothy after this, an. 52[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? St. Jerome, and also St. Chrysostom,[2] give another exposition of this passage. They looked upon all this to have been done by a contrivance and a collusion betwixt these two apostles, who had agreed beforehand that St. Peter should let himself be reprehended by St. Paul, (for this they take to be signified by the Greek text) and not that St. Peter was reprehensible;[3] so that the Jews seeing St. Peter publicly blamed, and not justifying himself, might for the future eat with the Gentiles. But St. Augustine vigorously opposed this exposition of St. Jerome, as less consistent with a Christian and apostolical sincerity, and with the text in this chapter, where it is called a dissimulation, and that Cephas or Peter walked not uprightly to the truth of the gospel. After a long dispute betwixt these two doctors, St. Jerome seems to have retracted his opinion, and the opinion of St. Augustine is commonly followed, that 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,[4] 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 offence to the Jєωιѕн converts; but if we examine the fact, he can scarce be excused from a venial indiscretion. (Witham) — I withstood, &c. The fault that is here noted in the conduct of St. Peter, was only a certain imprudence, in withdrawing himself from the table of the Gentiles, for fear of giving offence to the Jєωιѕн converts: but this in such circuмstances, when his so doing might be of ill consequence to the Gentiles, who might be induced thereby to think themselves obliged to conform to the Jєωιѕн way of living, to the prejudice of their Christian liberty. Neither was St. Paul’s reprehending him any argument against his supremacy; for is such cases an inferior may, and sometimes ought, with respect, to admonish his superior. (Challoner)


Galatians 2 – Haydock Commentary Online

If the pope can become a heretic (and I believe he can), then the following is possible:
c.  Similar to the actions of Christ's day, Annas and Chaiaphas, were heretics for the Jєωιѕн people.

And by this rending [of] his garments, [Caiaphas] shews that the Jews have lost the priestly glory, and that their High Priest’s throne was vacant. For by rending his garment he rent the veil of the Law which covered him.
(St. Jerome, Commentary on Matthew 26:65; quoted in St. Thomas Aquinas, ed., Catena Aurea: Commentary on the Four Gospels collected out of the Works of the Fathers Vol. I, Part III [Oxford: John Henry Parker, 1842], p. 926.)