For if I build again the things which I destroyed, I make myself a transgressor.
18. For if I build again. The reply consists of two parts. This is the first part, and informs us that the supposition now made is at variance with his whole doctrine, since he had preached the faith of Christ in such a manner as to connect with it the ruin and destruction of sin.
Peter came to Antioch eating freely with Gentile believers, as the Spirit had taught him; but when Jewish Christians arrived, he withdrew, and this hypocrisy I had to oppose to his face. His fault proved plainly that he was not superior to me, and so the papacy's claim to his infallibility falls to pieces.
AI summary
Commenting on Galatians 2:11-21
For if I build again the things which I destroyed,.... Which must be understood not of good things, for formerly he destroyed the faith of the Gospel, at least as much as in him lay, and now he built it up, established, and defended it; in doing which he did no evil, or made himself a transgressor, but the reverse; he showed himself a faithful...