Leviticus 16:4-6

Amplified Bible

⁴ He shall put on the holy linen tunic, and the linen undergarments shall be next to his body, and he shall be belted with the linen sash, and dressed with the linen turban (these are the holy garments). He shall bathe his body in water and put them on. ⁵ He shall take from the congregation of the Israelites [at their expense] two male goats as a sin offering and one ram as a burnt offering. ⁶ Then Aaron shall present the bull as the sin offering for himself, and make atonement for himself and for his house.