NUMBERS 18:3-9

³And they shall keep thy charge, and the charge of all the Tent: only they shall not come nigh unto the vessels of the sanctuary and unto the altar, that they die not, neither they, nor ye.

⁴And they shall be joined unto thee, and keep the charge of the tent of meeting, for all the service of the Tent: and a stranger shall not come nigh unto you.

⁵And ye shall keep the charge of the sanctuary, and the charge of the altar: that there be wrath no more upon the children of Israel.

⁶And I, behold, I have taken your brethren the Levites from among the children of Israel: to you they are a gift, given unto the LORD, to do the service of the tent of meeting.

⁷And thou and thy sons with thee shall keep your priesthood for every thing of the altar, and for that within the veil; and ye shall serve: I give you the priesthood as a service of gift: and the stranger that cometh nigh shall be put to death.

⁸And the LORD spake unto Aaron, And I, behold, I have given thee the charge of mine heave offerings, even all the hallowed things of the children of Israel, unto thee have I given them by reason of the anointing, and to thy sons, as a due for ever.

⁹This shall be thine of the most holy things, reserved from the fire: every oblation of theirs, even every meal offering of theirs, and every sin offering of theirs, and every guilt offering of theirs, which they shall render unto me, shall be most holy for thee and for thy sons.