Numbers 18:4 in the King James Version
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.
Context
3 They shall keep your commands and the duty of the whole Tent; only they shall not come near to the vessels of the sanctuary and to the altar, that they not die, neither they nor you.
4 They shall be joined to you and keep the responsibility of the Tent of Meeting, for all the service of the Tent. A stranger shall not come near to you.
5 “You shall perform the duty of the sanctuary and the duty of the altar, that there be no more wrath on the children of Israel.