2. and the LORD said to Moses: “Tell Aaron your brother that he must not enter at any time into the holy place inside the veil-canopy in front of the mercy seat that is on the ark so that he may not die, for I will appear in the cloud over the mercy seat.
3. “In this way Aaron is to enter into the sanctuary—with a young bull for a sin offering and a ram for a burnt offering.
4. He must put on a holy linen tunic, linen leggings are to cover his body, and he is to wrap himself with a linen sash and wrap his head with a linen turban. They are holy garments, so he must bathe his body in water and put them on.
5. He must also take two male goats from the congregation of the Israelites for a sin offering and one ram for a burnt offering.
6. Then Aaron is to present the sin offering bull which is for himself and is to make atonement on behalf of himself and his household.
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13. He must then put the incense on the fire before the LORD, and the cloud of incense will cover the mercy seat which is above the ark of the testimony, so that he will not die.
14. Then he is to take some of the blood of the bull and sprinkle it with his finger on the eastern face of the mercy seat, and in front of the mercy seat he is to sprinkle some of the blood seven times with his finger.
15. “He must then slaughter the sin offering goat which is for the people. He is to bring its blood inside the veil-canopy, and he is to do with its blood just as he did to the blood of the bull: He is to sprinkle it on the mercy seat and in front of the mercy seat.
16. So he is to make atonement for the holy place from the impurities of the Israelites and from their transgressions with regard to all their sins, and thus he is to do for the Meeting Tent which resides with them in the midst of their impurities.

based on NET Bible