Numbers 18:6

“Bring the tribe of Levi near and have them stand before Aaron the priest, that they may minister to him.

“You shall thus give the Levites to Aaron and to his sons; they are wholly given to him from among the sons of Israel.

and that He has brought you near, Korah, and all your brothers, sons of Levi, with you? And are you seeking for the priesthood also?

At that time Yahweh set apart the tribe of Levi to carry the ark of the covenant of Yahweh, to stand before Yahweh to minister for Him and to bless in His name to this day.

So Micah ordained the Levite, and the young man became his priest and lived in the house of Micah.

“Yet they shall be ministers in My sanctuary, having oversight at the gates of the house and ministering in the house; they shall slaughter the burnt offering and the sacrifice for the people, and they shall stand before them to minister to them.

Now when these things have been so prepared, the priests are continually entering the first part of the tabernacle performing the divine worship,