Numbers 1:47-53

47But the Levites after the tribe of their fathers were not numbered among them.

48For Jehovah had spoken to Moses, saying,

49Only thou shalt not number the tribe of Levi, neither take the sum of them among the children of Israel.

50But thou, appoint the Levites over the tabernacle of testimony, and over all the vessels thereof, and over all things that belong to it: they shall bear the tabernacle, and all its vessels; and they shall serve it, and round about the tabernacle shall they encamp;

51and when the tabernacle setteth forward, the Levites shall take it down; and when the tabernacle encampeth, the Levites shall set it up; and the stranger that cometh near shall be put to death.

52And the children of Israel shall encamp every man in his camp, and every man by his own standard, according to their hosts;

53but the Levites shall encamp round about the tabernacle of testimony, that there come not wrath upon the assembly of the children of Israel; and the Levites shall keep the charge of the tabernacle of testimony.