Leviticus 16:23-25

23“Aaron must then enter the Meeting Tent and take off the linen garments which he had put on when he entered the sanctuary, and leave them there.

24Then he must bathe his body in water in a holy place, put on his clothes, and go out and make his burnt offering and the people’s burnt offering. So he is to make atonement on behalf of himself and the people.

25“Then he is to offer up the fat of the sin offering in smoke on the altar,