Numbers 1:18-20

Lexham English Bible

¹⁸ and they summoned the entire community on the first day of the second month. And they registered themselves among their clans according to their families,^[a] according to the number of names from those twenty years old^[b] and above individually, ¹⁹ just as Yahweh commanded Moses. And he counted them in the desert of Sinai.

²⁰ The descendants of Reuben, the firstborn of Israel, their genealogies according to their clans, according to their families,^[c] according to the number of names, every male individually from twenty years old^[d] and above, everyone who is able to go to war: