(17) Sanctify them through thy truth.--Better, in Thy truth. Truth was the sphere in which their sanctification was to take place. They had through Christ received the Father's word, which was truth, and had passed into a new region of life, separate from the world (John 17:6-8; John 17:14-16). He has prayed that the Father would preserve them in this, and now He prays further that the Father would in this new region of life set them apart for the work to which He had sent them (John 17:18).

The idea at the root of the word rendered "sanctify," is not holiness, but separation. It is opposed not to what is impure, but to what is common, and is constantly used in the Greek of the Old Testament for the consecration of persons and things to the service of God. Hence our Lord can use it of Himself in John 10:36, and in this context (John 17:19; these are the only places where it occurs in St. John's writings). He was Himself "set apart and sent into the world." He has to send them into the world in the same way (John 17:18, and John 10:36), and prays that they may be in the same way consecrated for their work.

Thy word is truth.--There is a strong emphasis in the pronoun "Thy word is truth." This word they had kept (John 17:6-8). It had become the region of their life. They are to be the channels through which it is to pass to others (John 17:20). They are already in the higher sphere of truth, in which their entire consecration is to take place, when the gifts of the Holy Spirit shall descend upon them.

Verse 17. - Sanctify them; consecrate them (cf. John 10:36, of the sanctification of the Son by the Father to the work of effecting human redemption), separate them from the evil of the world, as for holy purposes. Devote them to the glorious cause. Let them be sacrifices on the altar. The ἁγιάζω, to sanctify, is not synonymous with καθαρίζω, to purify; α{γιος ισ not a contradiction of the defiled so much as of the purely natural, and involves the higher ends of grace (Exodus 29:1, 36; Exodus 40:13). The sanctification of the Old Testament is a ritual process effected by ceremonial observance; the sanctification of the New Testament is a spiritual process passing over heart and conscience and will, and is the work of the Divine Spirit. Meyer, Westcott, and others translate the next clause, in the truth, as the atmosphere in which the disciples dwell; but a large number of commentators, with Godet, take ἐν τῇ ἀληθείᾳ as equivalent to" by the aid of," with the instrumentality of, "the truth:" consecrate them, by revealing to them the reality, making known to them the truth. If they see the truth they will be discharged from the illusions of the world, the flesh, and the devil. (Luther takes ἐν τῇ ἀληθείᾳ adverbially, and as equivalent to "verily and indeed; but this cannot well be, seeing the article is present, and taking account of the subsequent definition of ἀληθεία, it becomes improbable.) But what is "truth"? what is the full expression of reality? how are we to know where to find it? Thy Logos (thy Word), the utterance of thy thought, is truth. If we can ever cognize what is the Divine thought about anything, we shall reach the absolute truth. What God troweth is truth per se. The Logos of God, the full, God-chosen utterance of the reality of truth, is the nearest approach to truth that we possess. This revelation of God is the closest correspondence with the reality. God sanctifies his children, consecrates them to the service of his kingdom by revealing the truth, by making known the otherwise transcendental facts of his kingdom. A long controversy has prevailed in the Church as to whether the Spirit's gracious operations are or are not limited by the operation of truth on the mind. Numerous assurances of the New Testament seem thus to limit the grace of God, or to measure it by the ordinary effect produced on the understanding by Divine truth; e.g. "Of his own will begat he us by the Word of truth;" the parable of the sower, and other Scriptures. But seeing that the regeneration, the conference of new and supernatural life, is set forth by images of resurrection and new creation, and as a purification of taste, bias, and desire, the gift of a new heart and right spirit, the voice of a heavenly sonship crying within us, "Abba, Father," and seeing that the ministration of the Spirit is variously directed and operative, and that there is shadowed forth an immediate work on the heart," back of consciousness" itself, and that the witness of the Spirit and the teaching and indwelling of the Holy Ghost are continually referred to, - we are loath to accept the dogma. The Spirit of God is not limited to the normal operations of the Word.

17:17-19 Christ next prayed for the disciples, that they might not only be kept from evil, but made good. It is the prayer of Jesus for all that are his, that they may be made holy. Even disciples must pray for sanctifying grace. The means of giving this grace is, through thy truth, thy word is truth. Sanctify them, set them apart for thyself and thy service. Own them in the office; let thy hand go with them. Jesus entirely devoted himself to his undertaking, and all the parts of it, especially the offering up himself without spot unto God, by the eternal Spirit. The real holiness of all true Christians is the fruit of Christ's death, by which the gift of the Holy Ghost was purchased; he gave himself for his church, to sanctify it. If our views have not this effect on us, they are not Divine truth, or we do not receive them by a living and a working faith, but as mere notions.Sanctify them through thy truth,.... The Syriac version introduces this petition, with the appellation "Abba, Father": and the sanctification prayed for regards the apostles, either as ministers of the word, and may intend their separation for their work and office; for which though they were sanctified or separated from their mother's womb, and by Christ when he sent them forth, yet were to have a fresh commission and unction after our Lord's resurrection, and upon his ascension to heaven; and also their qualification for it, with the truth of grace and doctrine, with holiness of heart and life, and with a preservation in the truth, by being kept faithful to it: or it may also regard them as Christians and believers, and intend a greater degree of the sanctification of the Spirit, which is imperfect in this life; for though sanctification in Christ is perfect, and so it is in the saints, as to parts, yet not as to degrees; which appears from the imperfection of faith, hope, love, and knowledge, from indwelling sin, being in the best of saints, from their necessities, from their disclaiming perfection, and their desires after it. Sanctification is a progressive work, which is carried on gradually; as is clear from the characters of regenerate ones, who are first newborn babes, then young men, and afterwards fathers in Christ; from the similes, by which it is expressed as seed which opens and grows up by degrees, and light which shines more and more unto the perfect day from exhortations to a concern for the growth of it, and prayers for it: and it is indeed continually carrying on, as may be concluded from the hand in which it is; and the progress and finishing of this work, as well as the beginning of it, are entirely the Lord's; and the way and means in which this is done, are by or through the truth of the Gospel:

thy word is truth; it is "peculiarly" so, as the Arabic version reads it. The Gospel is here meant, and is so called on account of its original, it comes from the God of truth; and because of the concern which Christ, who is the truth, has in it, he being the author, preacher, and sum and substance of it; and because the Spirit of truth has dictated it, leads into it, qualifies men to preach it, and makes it effectual: and because it contains all truth necessary to salvation, and nothing but truth, and particularly that eminent truth, salvation alone by Christ; and because it is opposed to the law, which is but a shadow, of which the good things in the Gospel are the substance: now this is the means both of the beginning, and increasing, and carrying on the work of sanctification in the hearts of God's people, as well as of an experimental knowledge of it; and an increase of that knowledge does more and more qualify the ministers of it for their ministerial work and service, which seems here chiefly designed.