Numbers 18:4-6

King James Version

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

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

⁶ And I, behold, I have taken your brethren the Levites from among the children of Israel: to you they are given as a gift for the Lord, to do the service of the tabernacle of the congregation.