Leviticus 16:1 WBT

¹  And the LORD spoke to Moses after the death of the two sons of Aaron, when they offered before the LORD, and died:

²  And the LORD said to Moses, Speak to Aaron thy brother, that he come not at all times into the holy [place] within the vail, before the mercy-seat, which [is] upon the ark; that he may not die: for I will appear in the cloud upon the mercy-seat.

³  Thus shall Aaron come into the holy [place]: with a young bullock for a sin-offering, and a ram for a burnt-offering.