Numbers 4:16

“This is the offering which Aaron and his sons shall bring near to Yahweh on the day when he is anointed; the tenth of an ephah of fine flour as a regular grain offering, half of it in the morning and half of it in the evening.

“So when the tabernacle is to set out, the Levites shall take it down; and when the tabernacle encamps, the Levites shall set it up. But the layman who comes near shall be put to death.

Then the Kohathites set out, carrying the holy objects; and the tabernacle was set up before their arrival.

“And they shall thus keep your responsibility and the responsibility of all the tent, but they shall not come near to the furnishings of the sanctuary and the altar, so that neither they nor you will die.

And the Levites were numbered from thirty years old and upward, and their number by census of men was 38,000.

“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.