Matthew Poole and continuators on John 17:19

19 And for their sakes I sanctifie my self , that they also might be sanctified through the truth .

I Sanctifie my self, here, is no more than I set my self apart, as a Sacrifice acceptable, and well-pleasing in the sight of God: and indeed sanctifying in the ancient notion of it under the Law, did ordinarily signifie the setting of persons and things apart to the special Service of God, which was done legally, by certain ritual performances and ceremonies, and is still done inwardly and Spiritually by Regeneration, and renewing of the hearts of men and women by the efficacious working of the Holy Ghost. Christ saith, that for his Disciples [illegible: 1 letter]ake he sanctified himself, being both the Priest and the Sacrifice.

Christ set apart himself as a Sacrifice for his people, that they might be sanctified, not onely our Eternal life and Happiness, but all the means to it fell within the Counsel of God; hence we are said to be chosen of Christ, that we should be holy, and without blame before him in love; and within the purchase of Christ; hence the Apostle saith, Eph. 5 25. That he gave himself for his Church, that he might sanctifie and cleanse it with the washing of water: and our Saviour here saith, that he set apart himself for a Sacrifice for our sins, that his people might be Sanctified through the truth; that is, by receiving the truth, not in their ears onely, but in their hearts, in the love of it, and bringing forth the fruits of it in all Holiness of life and conversation.

Marginal references: 1 Cor. 1.2, 30. 1 Thes. 4.7.; Or, truly Sanctified.