Dedicate is rendered “consecrate” in several translations (Moffatt, Goodspeed, New English Bible, New American Bible, Jerusalem Bible). The Greek verb used here is the same as in 10.36 (Good News Translation chose). The dedication is obviously to God, and Good News Translation (Dedicate … to yourself) and Barclay (“consecrate … to yourself”) make this explicit. Die Bibel im heutigen Deutsch has “make them your own.”
The clause Dedicate them to yourself represents a Greek expression traditionally translated “sanctify them” or, literally, “make them holy.” The biblical concept of sanctification always involves the dedication of something to the exclusive service of God. If God himself is involved in the act of sanctification, it would clearly be a matter of dedicating persons to himself, that is, to his own service or to be his own possession. In some languages there is no special term for “dedicate.” the only equivalent is “give.” One may say “give them to yourself,” but it may be more appropriate to use such an expression as “receive them to yourself” or “take them to yourself” or “make them yours.” The meaning of this final phrase fits well with certain renderings of a related Greek term traditionally translated “saints,” but more frequently rendered in modern translations “the people of God.”
By means of the truth (so also New American Bible) is rendered “by the truth” in a number of translations. Although it is possible to take this expression as purely adverbial (New English Bible alternative rendering “in truth”), it is doubtful that it has this meaning in the present context. In the Gospel of John Jesus himself is identified with the truth (14.6), and the truth has the power to act (note 8.32). The phrase by means of the truth poses two difficulties in some languages: (1) there may be no abstract noun meaning truth, and (2) it may be difficult to speak of truth as the means by which something is accomplished. The focus here is not essentially upon the abstract fact of the truth, but upon the content of the message, which is true. But even in this context truth can perhaps best be understood as “the truth about God,” himself, contained in the words God gave Jesus to communicate to his followers. The closest equivalent, therefore, in some languages is “by means of your words, which are true.”
Your word is truth is identical with the reading of one of the Septuagint manuscripts of Psalm 119.142. Elsewhere in the Gospel, Jesus himself is spoken of as the Word (1.14) and the truth (14.6).
Quoted with permission from Newman, Barclay M. and Nida, Eugene A. A Handbook on the Gospel of John. (UBS Handbook Series). New York: UBS, 1980. For this and other handbooks for translators see here .