Then he began to curse and to swear. In this third denial, Peter's unfaithfulness to his Master reached its utmost height. Not satisfied with swearing, he breaks out into cursing, by which he abandons his body and soul to destruction; for he prays that the curse of God may fall upon him, if he knows Christ. It is as much as if he had said, May I perish miserably, if I have any thing in common with the salvation of God! So much the more ought we to admire the goodness of Christ, who rescued his disciple from such fatal ruin, and healed him. Now this passage shows, that when a man falling through weakness of the flesh, denies the truth though he knows it, this does not amount to "blasphemy against the Holy Spirit" (Matthew 12:31, 32.) Peter had unquestionably heard from the mouth of the Lord how detestable treachery it is to deny him before men; and what dreadful vengeance, before God and before his angels, (Matthew 10:39 Luke 12:9) awaits those who, through a cowardly dread of the cross, abandon the confession of faith; and not without reason had he, a little before, preferred death and every kind of torment to denying Christ. Now, therefore, he throws himself down knowingly, and after previous warning; but afterwards he obtains pardon; from which it follows that he sinned through weakness and not through incurable malice. For he would willingly have rendered to Christ the duties of friendship which he owed him, had not fear extinguished the sparks of proper affection.

Then began he to curse - Peter was now irritated beyond endurance. He could no longer resist the evidence that he was known. It had been repeatedly charged on him. His language had betrayed him, and there was a positive witness who had seen him. He felt it necessary, therefore, to be still more decided, and he accordingly added to the sin of denying his Lord the deep aggravation of profane cursing and swearing, affirming what he must have known was false, that he knew not the man. Immediately then the cock crew - that is, the second crowing, or not far from three in the morning.

Then began he to curse and to swear - Rather, Then he began positively to affirm - καταθεματιζειν, from κατα intensive, and τιθημι, I lay down, place, affirm. But the common reading is καταναθεματιζειν, which signifies to wish curses on himself. The former reading is supported by almost every MS. of value, and is, beyond dispute, the true reading, and has been received by Griesbach into the text. The business is bad enough, but the common reading makes it worse. In Matthew 26:72, Peter is said to deny with an oath; here, he positively affirms and swears, probably by the name of God, for this is the import of the word ομνυειν. This makes the fourth and final gradation in the climax of Peter's fall. From these awful beginnings it is not unfair to conclude that Peter might have gone almost as far as Judas himself, had not the traitorous business been effected before. Yet all this evil sprung simply from the fear of man. How many denials of Christ and his truth have sprung since, from the same cause!
The cock crew - This animal becomes, in the hand of God, the instrument of awaking the fallen apostle, at last, to a sense of his fall, danger, and duty. When abandoned of God, the smallest thing may become the occasion of a fall; and, when in the hand of God, the smallest matter may become the instrument of our restoration. Let us never think lightly of what are termed little sins: the smallest one has the seed of eternal ruin in it. Let us never think contemptibly of the feeblest means of grace: each may have the seed of eternal salvation in it. Let us ever remember that the great Apostle Peter fell through fear of a servant maid, and rose through the crowing of a cock.

Then began he to (i) curse and to swear, [saying], I know not the man. And immediately the cock crew.
(i) He swore and cursed himself.

Then began he to curse, and to swear,.... He swore before, and now he began "to curse"; not Christ, as Saul compelled some to blaspheme him, who professed him, and as the Jews formerly cursed Christ, and his followers, in their synagogues: for Peter's crime was bad enough, it need not be made worse than it was: he could never call Jesus accursed; in so doing he would have sinned the sin against the Holy Ghost; but he cursed himself; "he began to imprecate himself", as the Arabic version renders it; he made dreadful imprecations and wishes; wished that all the miseries and calamities he could think of might fall upon him, if he was one of the disciples of Jesus of Nazareth, or knew anything of him: saying,
I know not the man; if I do, God do so to me, or more also: let vengeance light upon me; may I be the most miserable creature in the world, if I know anything of him,
and immediately the cock crew: as he was swearing and cursing in this manner; as soon as ever the words were out of his mouth, and he had in this sad and solemn manner three times denied that he knew Christ, or was ever with him, or a disciple of his. It is forbid, by a Jewish canon, to keep cocks at Jerusalem; it runs thus (c):
"they do not bring up cocks in Jerusalem, because of the holy things, neither do the priests in all the land of Israel, because of the purifications.
Whether this canon was then in being, or how it was dispensed with, or whether there was any particular providence in the cock being here now, and so nigh the high priest's palace, is not certain; but one there was: nor can the Jews deny that there were cocks at Jerusalem; for they themselves speak of a cock, (d), "that was stoned at Jerusalem",
(c) Misn. Bava Kama, c. 7. sect. 7. T. Bab. Bava Kama, fol. 82. 2. Abot R. Nathan, c. 35. Maimon. Hilch. Beth Habechirah, c. 7. sect. 14. Shalshelet Hakabala, fol. 9. 2. (d) T. Hieros Erubin, fol. 26. 1. Caphtor, fol. 42. 1.

He began to curse and to swear. Peter's third denial. He not only, with an oath, repeats what he had said in the second, but he affirms it with imprecations of divine wrath on himself if he spake not the truth. The gradations of guilt in the denials of Peter: (1) Ambiguous evasion; (2) distinct denial with a false oath; (3) awful abjuration with solemn imprecations on himself.
Immediately the cock crew. This was at the opening of the fourth or morning watch, at about three o'clock. The cock often crows about midnight, or not long after; and again always about the third hour after midnight, or three o'clock. This shows that the second trial of Jesus took place before the dawn.

Then began he to curse and to swear - Having now quite lost the reins, the government of himself.