15 Simon Peter followed Jesus, and so did another disciple. As this disciple was known to the high priest, he entered the court of the high priest along with Jesus, 16 while Peter stood outside at the door. So the other disciple, who was known to the high priest, went out and spoke to the maid who kept the door, and brought Peter in. 17 The maid who kept the door said to Peter, "Are not you also one of this man's disciples?" He said, "I am not." 18 Now the servants and officers had made a charcoal fire, because it was cold, and they were standing and warming themselves; Peter also was with them, standing and warming himself.
19 The high priest then questioned Jesus about his disciples and his teaching. 20 Jesus answered him, "I have spoken openly to the world; I have always taught in synagogues and in the temple, where all Jews come together; I have said nothing secretly. 21 Why do you ask me? Ask those who have heard me, what I said to them; they know what I said." 22 When he had said this, one of the officers standing by struck Jesus with his hand, saying, "Is that how you answer the high priest?" 23 Jesus answered him, "If I have spoken wrongly, bear witness to the wrong; but if I have spoken rightly, why do you strike me?" 24 Annas then sent him bound to Ca'iaphas the high priest.
25 Now Simon Peter was standing and warming himself. They said to him, "Are not you also one of his disciples?" He denied it and said, "I am not." 26 One of the servants of the high priest, a kinsman of the man whose ear Peter had cut off, asked, "Did I not see you in the garden with him?" 27 Peter again denied it; and at once 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.