John 13 - G. Campbell Morgan's Exposition on the Whole Bible

For a time our Lord now devoted Himself to His own, and in this connection we have the account of His washing the disciples' feet. The whole action was Eastern, and was the action of a slave: By what He did and said our Lord intended to emphasize that the supreme action of God is service, and that fellowship with Him demands such action on the part of His followers.

Then, in connection with the Pass over feast, Judas was excluded, and our Lord uttered the significant words, "Now is the Son of Man glorified," and this made possible our Lord's final instruction to His disciples. It was in this connection that Peter, strangely perplexed, asked Him the question, "Whither goest Thou?" to which our Lord first replied by showing Peter that he, Peter, could not at that time accompany Him on the pathway. When Peter protested, our Lord showed him that He knew all the weakness lurking within him better than he himself could know it, as He declared that before sunrise he would deny Him thrice.