Luke 22:32

I have prayed for thee - From the natural forwardness and impetuosity of thy own spirit, thou wilt be brought into the most imminent danger; but I have supplicated for thee, that thy faith may not utterly fail - ͅ , from , out, and , I fail, to fall utterly or entirely off. Peter' s faith did fail, but not utterly: he did fall, but he did not fall off, apostatize, or forsake his Master and his cause finally, as Judas did. Every body sees, from Peter' s denial of his Lord, that his faith did fail, and his great courage too; and yet they read, in the common translation, that Christ prayed that it might not fail: can they then conceive that our Lord' s prayer was heard? The translation which I have given above removes this embarrassment and apparent contradiction. It was certainly Peter' s advantage that our Lord did pray for him; but it was not so much for his honor that he should stand in need of such a prayer, beyond all others. Lightfoot.

When thou art converted - Restored to a sense of thy folly and sin, and to me and my cause - establish these thy brethren. All the disciples forsook Jesus and fled, merely through fear of losing their lives; Peter, who continued for a while near him, denied his Master with oaths, and repeated this thrice: our Lord seems to intimate that, after this fall, Peter would become more cautious and circumspect than ever; and that he should become uncommonly strong in the faith, which was the case; and that, notwithstanding the baseness of his past conduct, he should be a proper instrument for strengthening the feeble minded, and supporting the weak. His two epistles to the persecuted Christians show how well he was qualified for this important work.