Numbers 18:4-6

Revised Standard Version

⁴ They shall join you, and attend to the tent of meeting, for all the service of the tent; and no one else shall come near you. ⁵ And you shall attend to the duties of the sanctuary and the duties of the altar, that there be wrath no more upon the people of Israel. ⁶ And behold, I have taken your brethren the Levites from among the people of Israel; they are a gift to you, given to the Lord, to do the service of the tent of meeting.