And he is the propitiation— Rather the propitiatory sacrifice; the sin-offering, or sacrifice of atonement; for so the word 'Ιλασμος signifies both here and ch. 1 John 4:10. See on Romans 3:25. In this and the former verse, Jesus Christ is considered as being himself both the High-priest and the Sacrifice of atonement; and St. John having represented him as our Advocate with the Father, or our great High-priest gone within the veil to plead for us, further intimates, that he was also the great Christian Sacrifice or Sin-offering, and entered with his own blood within the veil, there to appear in the presence of God for us. Under the law the high-priest had never perfectly made an atonement, until he had entered within the veil, and sprinkled the blood before the mercy-seat. The slaying of the sacrifice, and offering it upon the altar, were previous steps; but the completion of the work was going within the veil, and there sprinkling the blood: thereby the high priest made an atonement for himself, for his household the priests, and for all the congregation of Israel. Leviticus 16:17.
In allusion hereto, our blessed Lord is here represented as entering into heaven, to plead our cause with the Father, after he had offered himself on the cross as a sacrifice for our sins; a view in which he is often represented, particularly in the epistle to the Hebrews. "He is the great propitiation for our sins, to whom, under that character, we have fled with cheerful confidence: and it is a joy to us to reflect, that he is not only the propitiation for ours but also [for the sins] of the whole world," &c. See the annotations on the epistle to the Romans for a full view of this subject, as it relates to the Heathen world.