Numbers 18:5

Then Moses said to Aaron and to his sons Eleazar and Ithamar, “Do not uncover your heads nor tear your clothes, so that you will not die and that He will not become wrathful against all the congregation. But your relatives, the whole house of Israel, shall weep over the burning which Yahweh has brought about.

“But the Levites shall camp around the tabernacle of the testimony so that there will be no wrath on the congregation of the sons of Israel. So the Levites shall keep charge of the tabernacle of the testimony.”

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

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?

And Moses said to Aaron, “Take your censer and put in it fire from the altar, and lay incense on it; then bring it quickly to the congregation and make atonement for them, for wrath has gone forth from Yahweh, the plague has begun!”

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.

“They shall enter My sanctuary; they shall come near to My table to minister to Me and keep the responsibility given by Me.

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