john 13:10 Jesus saith to him, He that is washed needeth not save to wash his feet, but is clean every whit: and ye are clean, but not all. - Free Bible Online

      10. He that is washed--in this thorough sense, to express which the word is carefully changed to one meaning to wash as in a bath.
      needeth not--to be so washed any more.
      save to wash his feet--needeth to do no more than wash his feet (and here the former word is resumed, meaning to wash the hands or feet).
      but is clean every whit--as a whole. This sentence is singularly instructive. Of the two cleansings, the one points to that which takes place at the commencement of the Christian life, embracing complete absolution from sin as a guilty state, and entire deliverance from it as a polluted life (Re 1:5; 1Co 6:11) --or, in the language of theology, Justification and Regeneration. This cleansing is effected once for all, and is never repeated. The other cleansing, described as that of "the feet," is such as one walking from a bath quite cleansed still needs, in consequence of his contact with the earth. (Compare Ex 30:18, 19). It is the daily cleansing which we are taught to seek, when in the spirit of adoption we say, "Our Father which art in heaven . . . forgive us our debts" (Mt 6:9, 12); and, when burdened with the sense of manifold shortcomings--as what tender spirit of a Christian is not?--is it not a relief to be permitted thus to wash our feet after a day's contact with the earth? This is not to call in question the completeness of our past justification. Our Lord, while graciously insisting on washing Peter's feet, refuses to extend the cleansing farther, that the symbolical instruction intended to be conveyed might not be marred.
      and ye are clean--in the first and whole sense.
      but not all--important, as showing that Judas, instead of being as true-hearted a disciple as the rest at first, and merely falling away afterwards--as many represent it--never experienced that cleansing at all which made the others what they were.

JFB.