Numbers 3:14-20

14And Jehovah spoke to Moses in the wilderness of Sinai, saying,

15Number the sons of Levi according to their fathers' houses, after their families; every male from a month old and upward shalt thou number them.

16And Moses numbered them, according to the commandment of Jehovah, — as he had been commanded.

17And these are the sons of Levi by their names: Gershon, and Kohath, and Merari.

18And these are the names of the sons of Gershon according to their families: Libni and Shimei.

19And the sons of Kohath according to their families: Amram and Izhar, Hebron and Uzziel.

20And the sons of Merari according to their families: Mahli and Mushi. These are the families of the Levites according to their fathers' houses.