Numbers 18:3-9

³They must serve you and the whole tent. However, they must not come near to anything in the holy place or connected with the altar, or they and also you will die.

⁴They must join you and take care of the tent of meeting, for all the work connected with the tent. A foreigner must not come near you.

⁵You must take responsibility for the holy place and for the altar so that my anger does not come on the people of Israel again.

⁶Look, I myself have chosen your fellow members of the Levites from among the descendants of Israel. They are a gift to you, given to me to do the work connected to the tent of meeting.

⁷But only you and your sons may exercise the priesthood regarding everything connected with the altar and everything inside the curtain. You yourselves must fulfill those responsibilities. I am giving you the priesthood as a gift. Any foreigner who approaches must be put to death.”

⁸Then Yahweh said to Aaron, “Look, I have given you the duty of handling the offerings raised up to me, and all the holy offerings that the people of Israel give to me. I have given these offerings to you and your sons as your ongoing share.

⁹This will belong to you from the most holy things that is kept from the fire. From every offering of theirs—every grain offering, every sin offering, and every guilt offering—they are set apart to you and to your sons.