Numbers 3:9 WEB

⁷  They shall keep his charge, and the charge of the whole congregation before the Tent of Meeting, to do the service of the tabernacle.

⁸  They shall keep all the furnishings of the Tent of Meeting, and the obligations of the children of Israel, to do the service of the tabernacle.

⁹  You shall give the Levites to Aaron and to his sons. They are wholly given to him on the behalf of the children of Israel.

¹⁰  You shall appoint Aaron and his sons, and they shall keep their priesthood. The stranger who comes near shall be put to death.'

¹¹  Yahweh spoke to Moses, saying,