Numbers 4:22-28

22“Also take a census of the sons of Gershon, by their fathers’ house, by their families.

23From thirty years old and above, even to fifty years old, you shall number them, all who enter to perform the service, to do the work in the tabernacle of meeting.

24This is the service of the families of the Gershonites, in serving and carrying:

25They shall carry the curtains of the tabernacle and the tabernacle of meeting with its covering, the covering of badger skins that is on it, the screen for the door of the tabernacle of meeting,

26the screen for the door of the gate of the court, the hangings of the court which are around the tabernacle and altar, and their cords, all the furnishings for their service and all that is made for these things: so shall they serve.

27“Aaron and his sons shall assign all the service of the sons of the Gershonites, all their tasks and all their service. And you shall appoint to them all their tasks as their duty.

28This is the service of the families of the sons of Gershon in the tabernacle of meeting. And their duties shall be under the authority of Ithamar the son of Aaron the priest.