Our Lord had terminated all question of testimony to man whether to the Jews or to the world. He now addresses Himself to His own in the world, the abiding objects of His unwavering love, as just about to leave this world for that place which suits His essential nature, as well as the glory destined Him by the Father. Accordingly our Lord, as thus going to heaven (new to Him as man), would prove His if possible increasing love to them, fully knowing what the enemy would effect through the wickedness of one of their number, as well as through the humbling sin of another. Hence He proceeds to give a visible sign of His new care which they would understand later. It was the needed service of love that He would carry on for them, when Himself out of this world and themselves in it; a service as real as any that He had ever done for them while He was in this world, and if possible, more important than any they had yet experienced. For He was not yet lifted up. But this ministration of His grace was also connected with His own portion in heaven. Accordingly it was to give them part with Him above outside the world. It was not divine goodness meeting them in the world, nor yet on the cross where God had to be glorified even as to sin. But as He was leaving the world for heaven whence He came, He would associate them with Himself where He was going. He was about to pass, though Lord of all, into the presence of God His Father in heaven, but would manifest Himself the servant of them all, even to the washing of their feet soiled in walking here below. The point therefore, was not here as on the cross suffering for their sins as sinners, but the service of love for saints, to fit them for having communion with Him, by cleansing them from defilements by the way before they join Him in that heavenly scene to which He was going at once. Such is the meaning suggested by the washing of the disciples' feet. In short, it is the word of God applied by the Holy Ghost, to deal with all that unfits for fellowship with the Father while Christ is above. It is His advocacy, to which the Holy Ghost answers here. Christ intercedes for us on high as identified with our every need here below, and the Holy Ghost meanwhile carrying it on by the work applied to us here to purify one by restoring him to the communion interrupted by a sin.
Ver. 10 explains the case clearly: "He that is bathed needeth not wash save his feet, but is wholly clean." There the initial bathing, the washing of regeneration and renewing of the Holy Spirit, which is never repeated. But there is the need of having the feet washed whenever defiled by the way. Neither refer to blood but to water, indispensable as it is to be washed from our sins by Christ's blood for redemption.