Numbers 4:23 ASV

²¹  And Jehovah spake unto Moses, saying,

²²  Take the sum of the sons of Gershon also, by their fathers' houses, by their families;

²³  from thirty years old and upward until fifty years old shalt thou number them; all that enter in to wait upon the service, to do the work in the tent of meeting.

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

²⁵  they shall bear the curtains of the tabernacle, and the tent of meeting, its covering, and the covering of sealskin that is above upon it, and the screen for the door of the tent of meeting,