Numbers 3:38

The Levites, however, were not numbered among them by their fathers’ tribe.

“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.

“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.”

Thus they shall keep responsibility of the tent of meeting, and responsibility of the holy place, and responsibility of the sons of Aaron their relatives, for the service of the house of Yahweh.