Leviticus 16:16

Make an atonement for the holy place. — The transgressions of the Israelites during the year not only defiled them, but also drew defilement upon the very sanctuary with its utensils, which was pitched in the midst of them. For this purpose the high priest during the second Temple thoroughly mixed the blood of the bullock with that of the goat, and went out into the Holy place which he inspected first.

And so shall he do for the tabernacle of the congregation. — Better, and so shall he do for the tent of meeting. He next cleansed by the same process the tent of meeting, or the court of the sanctuary, where the Israelites were usually admitted; that is, the high priest sprinkled the court and the altar of burnt offering which was in it eight times with the mingled blood of the bullock and goat.