John Chrysostom

(Hom. lxxxii) Or thus: For their sakes I sanctify Myself, i. e. I offer Myself as a sacrifice to Thee; for all sacrifices, and things that are offered to God, are called holy. And whereas this sanctification was of old in figure, (a sheep being the sacrifice,) but now in truth, He adds, That they also might be sanctified through the truth; i. e. For I make them too an oblation to Thee; either meaning that He who was offered up was their head, or that they would be offered up too: as the Apostle saith, Present your bodies a living sacrifice, holy. (Rom. 12:1)