Leviticus 16:3

But in this way Aaron shall come into the Holy Place: with a bull from the herd for a sin offering and a ram for a burnt offering .

“This is how Aaron is to enter the Most Holy Place: He must first bring a young bull for a sin offering and a ram for a burnt offering.

Thus shall Aaron come into the holy place : with a young bullock for a sin offering, and a ram for a burnt offering.