Numbers 4:27

4:27 “All the service of the Gershonites, whether carrying loads or for any of their work, will be at the direction of Aaron and his sons. You will assign them all their tasks as their responsibility.

Numbers 16:1

The Rebellion of Korah

16:1 Now Korah son of Izhar, the son of Kohath, the son of Levi, and Dathan and Abiram, the sons of Eliab, and On son of Peleth, who were Reubenites, took men