Numbers 4:21-28 - Duties Of The Gershonites
21 And Jehovah spoke to Moses, saying, 22 Take also the sum of the sons of Gershon, according to their fathers' houses, after their families. 23 From thirty years old and upward to fifty years old shalt thou number them; every one that cometh to labour in the work, to perform the service in the tent of meeting. 24 This shall be the service of the families of the Gershonites, in serving, and in carrying: 25 they shall carry the curtains of the tabernacle, and the tent of meeting, its covering, and the covering of badgers' skin that is above upon it, and the curtain of the entrance to the tent of meeting, 26 and the hangings of the court, and the curtain of the entrance, of the gate of the court, which surroundeth the tabernacle and the altar, and the cords thereof, and all the instruments of their service; and all that is to be done for these things shall they perform.
27 At the commandment of Aaron and his sons shall be all the service of the sons of the Gershonites, in all their carrying, and in all their service; and ye shall appoint unto them in charge all their carrying. 28 This is the service of the families of the sons of Gershon in the tent of meeting, and their charge shall be under the hand of Ithamar the son of Aaron the priest.