Leviticus 16:2-4

American Standard Version

² and Jehovah said unto Moses, Speak unto Aaron thy brother, that he come not at all times into the holy place within the veil, before the mercy-seat which is upon the ark; that he die not: for I will appear in the cloud upon the mercy-seat. ³ Herewith shall Aaron come into the holy place: with a young bullock for a sin-offering, and a ram for a burnt-offering. ⁴ He shall put on the holy linen coat, and he shall have the linen breeches upon his flesh, and shall be girded with the linen girdle, and with the linen ^[a]mitre shall he be attired: they are the holy garments; and he shall bathe his flesh in water, and put them on.