3But 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.
Leviticus 16:3 introduces the sacrifices needed for the high priest as well as the people as he prepares to enter the Tabernacle on the Day of Atonement. Additionally, this verse stipulates the clothing that was to be worn by the high priest.
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.