Numbers 18
6 Ref `And I, lo, I have taken your brethren the Levites from the midst of the sons of Israel; to you a gift they are given by Jehovah, to do the service of the tent of meeting;
7 Ref and thou, and thy sons with thee, do keep your priesthood, for everything of the altar, and within the vail, and ye have served; a service of gift I make your priesthood; and the stranger who is coming near is put to death.'