John Calvin on John 18:27

27. Immediately the coch crew. The Evangelist mentions the crowing of the coch, in order to inform us, that Peter was warned by God at the very time; and for this reason the other Evangelists tell us, that he then remembered the words of the Lord, (Matthew 26:75; Mark 14:72,) though Luke relates that the mere crowing of the cock did not produce any effect on Peter, till Christ looked at him, (Luke 22:61.) Thus, when any person has once begun to fall through the suggestions of Satan, no voice, no sign, no warning, will bring him back, until the Lord himself cast his eyes upon him.

John 18:28-32

28. Then they lead Jesus from Caiaphas into the hall of the governor; “In Praetorium;” — “au Pretoire;” — “into the Pretorium.” and it was early in the morning; and they themselves did not enter into the hall, that they might not be defiled, but might eat the passover “L’agneau de pasque;” — “the paschal lamb.” 29. Pilate therefore went out to them, and said, What accusation do you bring against this man? 30. They answered and said to him, If he were not a malefactor, we would not have delivered him to thee. 31. Pilate therefore said to them, Take you him, and judge him according to your law. The Jews therefore said to him, We are not allowed to put any man to death: 32. That the word of Jesus might be fulfilled, which he had spoken, signifying by what death he should die.