For atonement, as well for the priests as for the altar; both which, as they were or might be polluted, so they needed the sprinkling of this blood to sanctify them, to show that all persons and things were fitted for God's service, and accepted by him only for and through the blood of Christ.
Related Commentaries of Exodus 29:36
Exodus 29:36
36 And thou shalt offer every day a bullock for a sin offering for atonement: and thou shalt cleanse the altar, when thou hast made an atonement for it, and thou shalt anoint it, to sanctify it.