Leviticus 16:15-17

15“When he slaughters the male goat for the people’s sin offering and brings its blood inside the curtain, he will do the same with its blood as he did with the bull’s blood: He is to sprinkle it against the mercy seat and in front of it.

16He will make atonement for the most holy place in this way for all their sins because of the Israelites’ impurities and rebellious acts. He will do the same for the tent of meeting that remains among them, because it is surrounded by their impurities.

17No one may be in the tent of meeting from the time he enters to make atonement in the most holy place until he leaves after he has made atonement for himself, his household, and the whole assembly of Israel.