Numbers 3:15 in the King James Version
Number the children of Levi after the house of their fathers, by their families: every male from a month old and upward shalt thou number them.
Context
14 The 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.”
16 Moses counted them according to the LORD’s word, as he was commanded.