Leviticus 16:3, 6
Leviticus 16:3 AMP
Aaron [as high priest] shall enter the Holy Place in this way: with [the blood of] a young bull as a sin offering and [the blood of] a ram as a burnt offering.
Leviticus 16:6 AMP
Then Aaron shall present the bull as the sin offering for himself, and make atonement for himself and for his house.