Numbers 4:23

20 and they go not in to see when the holy thing is swallowed, that they have died.`

21 And Jehovah speaketh unto Moses, saying,

22 `Take up the sum of the sons of Gershon also by the house of their fathers, by their families;

23 from a son of thirty years and upward, till a son of fifty years thou dost number them, every one who is going in to serve the host, to do the service in the tent of meeting.

24 `This [is] the service of the families of the Gershonite, to serve -- and for burden,

25 and they have borne the curtains of the tabernacle, and the tent of meeting, its covering, and the covering of the badger [skin] which [is] on it above, and the vail at the opening of the tent of meeting,

26 and the hangings of the court, and the vail at the opening of the gate of the court which [is] by the tabernacle, and by the altar round about, and their cords, and all the vessels of their service, and all that is made for them -- and they have served.