Leviticus 16:15-16

Then shall he kill the goat of the sin-offering, that is for the people, and bring his blood within the veil, and do with his blood as he did with the blood of the bullock, and sprinkle it upon the mercy-seat, and before the mercy-seat: and he shall make atonement for the holy place, because of the uncleannesses of the children of Israel, and because of their transgressions, even all their sins: and so shall he do for the tent of meeting, that dwelleth with them in the midst of their uncleannesses.