(7) What I do thou knowest not now.--Here both pronouns are emphatic, and convey a rebuke to Peter. His words had almost implied that the Lord's .act was wholly out of place, as of one who knew not what he was doing. The opposite was really the case. "What I do thou knowest not now."

But thou shalt know hereafter--i.e., in the teaching which is to follow (John 13:13-17). The word rendered "hereafter" is different from that rendered "afterwards" in John 13:36. The precise meaning is "after these things." The sense, then, is "What I do thou knowest not now; but thou shalt come to know presently." (Comp. John 13:17.)

Verses 7, 8. - Jesus answered and said to him, That which I am doing thou knowest not now - thou hast not absolute knowledge of, thou hast not seen through as yet; but after these things, afterwards when I shall have completed my present undertaking, thou (γνώσῃ) shalt come by clear proof and full discovery and intimate acquaintance to understand. This is sometimes referred to the subsequent illumination of the Holy Spirit, or even to the higher life of the future world (Luthardt), but the above interpretation is more consonant with the context. The μετὰ ταῦτα may (as Westcott suggests) point to the whole manifestation of love as it should complete itself on the cross, and become illumined by the Resurrection and by the gift of the Spirit, when the same mind should be put into Peter that was in Christ Jesus; consequently we may reasonably apply this great word to many of our earthly experiences. God's ways, Christ's government of his Church, and the mystery of our lot, are often so puzzling that we cannot be said to know them objectively or absolutely. We know (γινώσκομεν) but in part, and see (βλέπομεν) by means of a mirror (1 Corinthians 13:12); but eventually in the fulness of the Divine manifestation we shall know (ἐπιγνωσόμεθα) completely, subjectively, in the depths of our personal consciousness. Peter saith to him, with mere emphasis than before, with an intensity of double negative and εἰς τὸν αἰῶνα, Thou shalt not ever wash my feet - "not while eternity lasts." "A praiseworthy modesty," says Calvin, "were it not that with God obedience is better than worship." This vehement, Peter-like burst showed that even yet he had not learned his profound dependence upon his Lord. Exuberant utterance of a love which in its superlative enthusiasm was in danger of severing the relation between his Lord and himself, elicited from Christ a reply which went far Beneath this purely symbolic washing, and gave even to it a moral significance which it had not possessed before. Jesus answered, If I wash thee (not thy feet) not, thou hast no part with me - no μέρος, no portion, no share, no communion, no common inheritance with me in the honors and blessings of the kingdom. This may be understood in two ways: either, "If I do not by my grace cleanse you from your defilement, wash you in a deeper sense, in a more abundant and effectual manner than by giving you this practical lesson, there is utter misunderstanding of my relation to you - you have no part nor share with me." And this ver. 11 seems to favor. Hengstenberg strongly defends this view as a reference by Christ to his power on earth to forgive sins, and confer the pure and new nature (cf. Psalm 51:4, 9-11); and this doubtless lies in the solemn tone of the Lord. A refusal to accept the Divine cleansing is the only ground of exclusion from the benefits of the bloodshedding. Still another more obvious meaning arises, "If you refuse this manifestation of humble love from me, if you put your own pride between yourself and me, if you disdain this act of self-surrender, claiming to understand me and our mutual relations better than I, you have no part with me. This is a symbol of my love to you, and of what is to be your love to one another (ver. 15); if you refuse to accept it from me, you will then have no part with me in the manifestation of the spirit of self-sacrificing love which I have come to inaugurate." Peter must learn the beauty and glory of service for the sake of others; and if he were unable to understand and accept this act of love, he must separate himself from all share in the Master's work. This truth dawned upon him, but only in part, and it led to the extraordinary revulsion of feeling which followed.

13:1-17 Our Lord Jesus has a people in the world that are his own; he has purchased them, and paid dear for them, and he has set them apart for himself; they devote themselves to him as a peculiar people. Those whom Christ loves, he loves to the end. Nothing can separate a true believer from the love of Christ. We know not when our hour will come, therefore what we have to do in constant preparation for it, ought never to be undone. What way of access the devil has to men's hearts we cannot tell. But some sins are so exceedingly sinful, and there is so little temptation to them from the world and the flesh, that it is plain they are directly from Satan. Jesus washed his disciples' feet, that he might teach us to think nothing below us, wherein we may promote God's glory, and the good of our brethren. We must address ourselves to duty, and must lay aside every thing that would hinder us in what we have to do. Christ washed his disciples' feet, that he might signify to them the value of spiritual washing, and the cleansing of the soul from the pollutions of sin. Our Lord Jesus does many things of which even his own disciples do not for the present know the meaning, but they shall know afterward. We see in the end what was the kindness from events which seemed most cross. And it is not humility, but unbelief, to put away the offers of the gospel, as if too rich to be made to us, or too good news to be true. All those, and those only, who are spiritually washed by Christ, have a part in Christ. All whom Christ owns and saves, he justifies and sanctifies. Peter more than submits; he begs to be washed by Christ. How earnest he is for the purifying grace of the Lord Jesus, and the full effect of it, even upon his hands and head! Those who truly desire to be sanctified, desire to be sanctified throughout, to have the whole man, with all its parts and powers, made pure. The true believer is thus washed when he receives Christ for his salvation. See then what ought to be the daily care of those who through grace are in a justified state, and that is, to wash their feet; to cleanse themselves from daily guilt, and to watch against everything defiling. This should make us the more cautious. From yesterday's pardon, we should be strengthened against this day's temptation. And when hypocrites are discovered, it should be no surprise or cause of stumbling to us. Observe the lesson Christ here taught. Duties are mutual; we must both accept help from our brethren, and afford help to our brethren. When we see our Master serving, we cannot but see how ill it becomes us to domineer. And the same love which led Christ to ransom and reconcile his disciples when enemies, still influences him.Jesus answered and said unto him,.... Christ replies,

what I do, thou knowest not now: Peter knew that he was about to wash his feet, and the rest of his disciples, but he did not know the meaning and mystery of it, what Christ designed by it, and what instruction they were to receive from it,

but thou shalt know hereafter; as he did, when he had performed this service, and explained it to him. This may teach us, under dark providences, the meaning of which is not yet known by us, to wait the Lord's own time, to make things clear and plain to us, and in the mean time patiently submit to the divine will.