Numbers 3:15
“Count the children of Levi by their fathers’ houses, by their families. You shall count every male from a month old and upward.”
World English Bible (Public Domain)
In context
Before · Numbers 3:13–14
13for all the firstborn are mine. On the day that I struck down all the firstborn in the land of Egypt I made holy to me all the firstborn in Israel, both man and animal. They shall be mine. I am the LORD.” 14The LORD spoke to Moses in the wilderness of Sinai, saying,
15“Count the children of Levi by their fathers’ houses, by their families. You shall count every male from a month old and upward.”