15 Simon Peter followed Jesus, as did another disciple. Now that disciple was known to the high priest, and entered in with Jesus into the court of the high priest; 16 but Peter was standing at the door outside. So the other disciple, who was known to the high priest, went out and spoke to her who kept the door, and brought in Peter. 17 Then the maid who kept the door said to Peter, “Are you also one of this man’s disciples?”
He said, “I am not.” 18 Now the servants and the officers were standing there, having made a fire of coals, for it was cold. They were warming themselves. Peter was with them, standing and warming himself.
19 The high priest therefore asked Jesus about his disciples, and about his teaching. 20 Jesus answered him, “I spoke openly to the world. I always taught in synagogues, and in the temple, where the Jews always meet. I said nothing in secret. 21 Why do you ask me? Ask those who have heard me what I said to them. Behold, these know the things which I said.” 22 When he had said this, one of the officers standing by slapped Jesus with his hand, saying, “Do you answer the high priest like that?” 23 Jesus answered him, “If I have spoken evil, testify of the evil; but if well, why do you beat me?” 24 Annas sent him bound to Caiaphas, the high priest.
25 Now Simon Peter was standing and warming himself. They said therefore to him, “You aren’t also one of his disciples, are you?”
He denied it, and said, “I am not.” 26 One of the servants of the high priest, being a relative of him whose ear Peter had cut off, said, “Didn’t I see you in the garden with him?” 27 Peter therefore denied it again, and immediately the rooster crowed.
Matthew Henry's Commentary on John 18:15-27
Commentary on John 18:13-27
(Read John 18:13-27)
Simon Peter denied his Master. The particulars have been noticed in the remarks on the other Gospels. The beginning of sin is as the letting forth of water. The sin of lying is a fruitful sin; one lie needs another to support it, and that another. If a call to expose ourselves to danger be clear, we may hope God will enable us to honour him; if it be not, we may fear that God will leave us to shame ourselves. They said nothing concerning the miracles of Jesus, by which he had done so much good, and which proved his doctrine. Thus the enemies of Christ, whilst they quarrel with his truth, wilfully shut their eyes against it. He appeals to those who heard him. The doctrine of Christ may safely appeal to all that know it, and those who judge in truth bear witness to it. Our resentment of injuries must never be passionate. He reasoned with the man that did him the injury, and so may we.