Numbers 1:51-53

⁵¹'And in the journeying of the tabernacle, the Levites take it down, and in the encamping of the tabernacle, the Levites raise it up; and the stranger who is coming near is put to death.'

⁵²And the sons of Israel have encamped, each by his camp, and each by his standard, by their hosts;

⁵³and the Levites encamp round about the tabernacle of the testimony; and there is no wrath on the company of the sons of Israel, and the Levites have kept the charge of the tabernacle of the testimony.