John 17:19 - Clarke's commentary and critical notes on the Bible

And for their sakes I sanctify myself, that they also might be sanctified through the truth. I sanctify myself - I consecrate and devote myself to death - that I may thereby purchase eternal salvation for them. There seems to be here an allusion to the entering of the high priest into the holy of holies, when, having offered the sacrifice, he sprinkled the blood before the ark of the covenant. So Jesus entered into the holiest of all by his own blood, in order to obtain everlasting redemption for men: see Hebrews 9:11-13. The word, ἁγιαζω, to consecrate or sanctify, is used in the sense of devoting to death, in Jeremiah 12:3, both in the Hebrew and in the Septuagint: the Hebrew קדש signifies also to sacrifice.