John Chrysostom
Catena Aurea · Johannesevangelium 17
I have given them thy word; and the world hath hated them, because they are not of the world, even as I am not of the world. I pray not that thou shouldest take them out of the world, but that thou shouldest keep them from the evil. They are not of the world, even as I am not of the world. Sanctify them through thy truth; thy word is truth. As thou hast sent me into the world, even so have I also sent them into the world. And for their sakes I sanctify myself, that they also might be sanctified through the truth.
(Hom. lxxxii) Or thus: Sanctify them in Thy truth; i. e. Make them holy, by the gift of the Holy Spirit, and sound doctrines: for sound doctrines give knowledge of God, and sanctify the soul. And as He is speaking of doctrines, He adds, Thy word is truth, i. e. there is in it no lie, nor any thing typical, or bodily. Again, Sanctify them in Thy truth, may mean, Separate them for the ministry of the word, and preaching.