Leviticus 16:1-6

¹And the Lord spake with Mosheh after the two sons of Aharon were dead, who offered the strange fire before the Lord, and died;

²And the Lord said unto Mosheh, Speak with Aharon thy brother, that he may not enter at any time into the Holy Place within the veil before the mercy seat which is upon the ark, that he die not; for in the cloud will I reveal Myself over the mercy seat.

³With this shall Aharon enter the holy place: With a young bullock for a sin offering, and a ram for a burnt offering.

⁴With the holy linen vesture shall he be clothed, and linen drawers shall be upon his flesh, and with the linen girdle shall he be bound, and the linen mitre shall be upon his head: these are holy garments; and he shall wash his flesh in water, and then put them on.

⁵And of the congregation of the sons of Israel let him take two kids of the goats for a sin offering, and one ram for a burnt offering.

⁶And Aharon shall offer the bullock of the sin offering for himself, and make atonement for himself and for the men of his house.