Barnes New Testament Notes

Verse 8. Thou shalt never wash my feet. This was a decided and firm expression of his reverence for his Mater, and yet it was improper. Jesus had just declared that it had a meaning, and that he ought to submit to it. We should yield to all the plain and positive requirements of God, even if we cannot now see how obedience would promote his glory.

If I wash thee not. This had immediate reference to the act of washing his feet; and it denotes that if Peter had not so much confidence in him as to believe that an act which he performed was proper, though he could not see its propriety -- if he was not willing to submit his will to that of Christ and implicitly obey him, he had no evidence of piety. As Christ, however, was accustomed to pass from temporal and sensible objects to those which were spiritual, and to draw instruction from whatever was before him, some have supposed that he here took occasion to state to Peter that if his soul was not made pure by him he could not be his follower. Washing is often thus put as an emblem of moral purification, 1 Co 6:11; Tit 3:5, 6.

This is the meaning, also, of baptism. If this was the sense in which Jesus used these words, it denotes that unless Christ should purify Peter, he could have no evidence that he was his disciple. "Unless by my doctrine and spirit I shall purify you, and remove your pride (Mt 26:33), your want of constant watchfulness (Mt 26:40), your anger (Mt 26:51), your timidity and fear (Mt 26:70,74), you can have no part in me" (Grotius).

Hast no part with me. Nothing in common with me. No evidence of possessing my spirit, of being interested in my work, and no participation in my glory:

{h} "If I wash thee not" 1 Co 6:11; Eph 5:26; Tit 3:5