Matthew
Matthew 26:74ESV·traditional attribution

Then he began to invoke a curse on himself and to swear, “I do not know the man.” And immediately the rooster crowed.

John Calvin Reformed @genevareformer

74. 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.

John Gill Reformed Baptist @doctorgill

And Peter remembered the words of Jesus,.... Forgetfulness of God, of his works, of his words, and of his law, of his revealed mind and will, is often the cause of sin; and a remembrance of things is necessary to the recovery of a fallen or backsliding professor; as, of what he is fallen from, of the love and kindness of God formerly shown to...

Albert Barnes Presbyterian @notesbybarnes

Verse 74. Then began he to curse, etc. 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.