John 18:16

And that Peter would have also entered had he been permitted, he shows by the sequel; for when he went out, and bade the damsel who kept the door bring in Peter, he straightway came in. But why did he not bring him in himself? He clung to Christ, and followed Him; on this account he bade the woman bring him in.

He stood without, as being about to deny his Lord. He was not in Christ, who dared not confess Christ.

"But Jesus was followed," he says, "by Simon Peter, and another disciple." Who that other disciple is, we cannot affirm with confidence, because it is left unnoticed here. But it is in this way that John usually refers to himself, with the addition, "whom Jesus loved." Perhaps, therefore, it is he also in the present case; but whoever it is, let us look at what follows. "And that disciple," he says, "was known unto the high priest, and went in with Jesus into the palace of the high priest; but Peter stood at the door without. Then went out that other disciple, who was known unto the high priest, and spake unto her that kept the door, and brought in Peter. Then saith the damsel that kept the door unto Peter, Art thou also one of this man's disciples? He saith, I am not." Lo, the pillar of greatest strength has at a single breath of air trembled to its foundations. Where is now all that boldness of the promiser, and his overweening confidence in himself beforehand? What now of those words, when he said, "Why cannot I follow Thee now? I will lay down my life for Thy sake." Is this the way to follow the Master, to deny his own discipleship? is it thus that one's life is laid down for the Lord, when one is frightened at a maid-servant's voice, lest it should compel us to the sacrifice? But what wonder, if God foretold what was true, and man presumptuously imagined what was false? Assuredly in this denial of the Apostle Peter, which had now entered on its first stage, we ought to take notice that not only is Christ denied by one who says that He is not Christ, but by him also who, while really a Christian, himself denies that he is so. For the Lord said not to Peter, Thou shall deny that thou art my disciple; but, "Thou shall deny me." Him, therefore, he denied, when he denied that he was His disciple. And what else did such a form of denial imply, but that of his own Christianity?