Numbers 4:21-33

Then the LORD spoke to Moses, saying, “Take a census of the sons of Gershon also, by their fathers’ households, by their families; from thirty years and upward to fifty years old, you shall number them; all who enter to perform the service to do the work in the tent of meeting. This is the service of the families of the Gershonites, in serving and in carrying: they shall carry the curtains of the tabernacle and the tent of meeting with its covering and the covering of porpoise skin that is on top of it, and the screen for the doorway of the tent of meeting, and the hangings of the court, and the screen for the doorway of the gate of the court which is around the tabernacle and the altar, and their cords and all the equipment for their service; and all that is to be done, they shall perform. All the service of the sons of the Gershonites, in all their loads and in all their work, shall be performed at the command of Aaron and his sons; and you shall assign to them as a duty all their loads. This is the service of the families of the sons of the Gershonites in the tent of meeting, and their duties shall be under the direction of Ithamar the son of Aaron the priest. “As for the sons of Merari, you shall number them by their families, by their fathers’ households; from thirty years and upward even to fifty years old, you shall number them, everyone who enters the service to do the work of the tent of meeting. Now this is the duty of their loads, for all their service in the tent of meeting: the boards of the tabernacle and its bars and its pillars and its sockets, and the pillars around the court and their sockets and their pegs and their cords, with all their equipment and with all their service; and you shall assign each man by name the items he is to carry. This is the service of the families of the sons of Merari, according to all their service in the tent of meeting, under the direction of Ithamar the son of Aaron the priest.”