15 Simon Peter and another disciple followed Jesus. Since that disciple was known to the high priest, he went with Jesus into the courtyard of the high priest, 16 but Peter was standing outside at the gate. So the other disciple, who was known to the high priest, went out, spoke to the woman who guarded the gate, and brought Peter in. 17 The woman said to Peter, "You are not also one of this man's disciples, are you?" He said, "I am not." 18 Now the slaves and the police had made a charcoal fire because it was cold, and they were standing around it and warming themselves. Peter also was standing with them and warming himself.
19 Then the high priest questioned Jesus about his disciples and about his teaching. 20 Jesus answered, "I have spoken openly to the world; I have always taught in synagogues and in the temple, where all the Jews come together. I have said nothing in secret. 21 Why do you ask me? Ask those who heard what I said to them; they know what I said." 22 When he had said this, one of the police standing nearby struck Jesus on the face, saying, "Is that how you answer the high priest?" 23 Jesus answered, "If I have spoken wrongly, testify to the wrong. But if I have spoken rightly, why do you strike me?" 24 Then Annas sent him bound to Caiaphas the high priest.
25 Now Simon Peter was standing and warming himself. They asked him, "You are not also one of his disciples, are you?" He denied it and said, "I am not." 26 One of the slaves of the high priest, a relative of the man whose ear Peter had cut off, asked, "Did I not see you in the garden with him?" 27 Again Peter denied it, and at that moment the cock 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.