Numbers 18:1-8

1And Jehovah said unto Aaron, Thou and thy sons and thy fathers’ house with thee shall bear the iniquity of the sanctuary; and thou and thy sons with thee shall bear the iniquity of your priesthood. 2And thy brethren also, the tribe of Levi, the tribe of thy father, bring thou near with thee, that they may be joined unto thee, and minister unto thee: but thou and thy sons with thee shall be before the tent of the testimony. 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 Jehovah, to do the service of the tent of meeting. 7And thou and thy sons with thee shall keep your priesthood for everything 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 Jehovah spake unto Aaron, And I, behold, I have given thee the charge of my 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 portion for ever.