Numbers 3:21-26

To Gershon belonged the clan of the Libnites and the clan of the Shimeites; these were the clans of the Gershonites. Their listing according to the number of all the males from a month old and upward was 7,500. The clans of the Gershonites were to camp behind the tabernacle on the west, with Eliasaph, the son of Lael as chief of the fathers’ house of the Gershonites. And the guard duty of the sons of Gershon in the tent of meeting involved the tabernacle, the tent with its covering, the screen for the entrance of the tent of meeting, the hangings of the court, the screen for the door of the court that is around the tabernacle and the altar, and its cords—all the service connected with these.