Numbers 3:15
Number the children of Levi after the house of their fathers, by their families: every male from a month old and upward shall you number them.
ā The Restored Word Bible
Context
13 Because all the firstborn mine; on the day that I smote all the firstborn in the land of Egypt I hallowed unto me all the firstborn in Israel, both man and beast: mine shall they be: I the Yahuah.
14 And the Yahuah spake unto Moses in the wilderness of Sinai, saying,
15 Number the children of Levi after the house of their fathers, by their families: every male from a month old and upward shall you number them.
16 And Moses numbered them according to the word of the Yahuah, as he was commanded.
17 And these were the sons of Levi by their names; Gershon, and Kohath, and Merari.