John 18:25
And Simon Peter stood and warmed himself. They said therefore unto him, Art not thou also one of his disciples? He denied it, and said, I am not. And Simon Peter stood and warmed himself. They said therefore unto him, Art not thou also one of his disciples? He denied it, and said, I am not.
This moment belongs to the humiliation of Jesus while He was being examined at the high priest's palace, before Annas and the court of Caiaphas, as part of the great trial of His betrayal and condemnation. That trial was one for which He had prepared His faithful disciples by letting them witness earlier followers turn away from Him. In the verse Peter is standing warming himself among his Master's enemies, acting a lie by pretending indifference and trying to hide that he followed Jesus.
He could not restrain expressions of indignation at the abuse heaped upon his Master, and that drew attention to him a second time and led to the questioning about being a disciple. The questioning records Peter's second denial of Jesus. Those who held it as the third denial taught that it was driven by fear for his safety. When charged with being a follower of Jesus and one of His disciples, he denied his discipleship with an oath, with cursing and swearing to make the denial convincing. Then the cock crowed the second time, but he did not hear it because he was thoroughly intent on carrying out the indifferent character he had assumed.
By disguising his faith to avoid suffering, shame or scorn and by associating with those opposed to his Master, Peter put himself in the way of temptation, so his denial came not in open conflict but under the scorn and pressure of those around him. He failed to witness for Jesus when put to the test because he trusted in himself, fearing ridicule, reproach and danger, and Satan suggested the words he used to deny his Lord, showing the danger of self-confidence. His denial pierced Jesus' heart more deeply than the mockery and accusations of His enemies.
Jesus' sorrowful, reproving look brought Peter to remember Jesus' warning and his own confident promise, melted his heart, and led him to bitter weeping and repentance, reconversion, and fresh self-giving to his Saviour. His sorrow humbled him and fitted him to sympathize with the weak and erring, warn the presumptuous, and strengthen his brethren, and as a converted man to become a bold witness for Christ. The verse warns that ridicule or fear of reproach and suffering can lead people who would stand firm in open conflict to deny their faith in practice, and concealing faith for such reasons is itself a denial of the Lord. Those who yield under such pressure may then be despised by the very people who tempted them.