Numbers 4:37-39

Revised Standard Version Catholic Edition

³⁷ This was the number of the families of the Ko′hathites, all who served in the tent of meeting, whom Moses and Aaron numbered according to the commandment of the Lord by Moses.

³⁸ The number of the sons of Gershon, by their families and their fathers’ houses, ³⁹ from thirty years old up to fifty years old, every one that could enter the service for work in the tent of meeting—