Numbers 1:17-19

Revised Standard Version Catholic Edition

¹⁷ Moses and Aaron took these men who have been named, ¹⁸ and on the first day of the second month, they assembled the whole congregation together, who registered themselves by families, by fathers’ houses, according to the number of names from twenty years old and upward, head by head, ¹⁹ as the Lord commanded Moses. So he numbered them in the wilderness of Sinai.