Numbers 26:4

4 from twenty years old and upward as the Lord commanded Moses. And the sons of Israel that came out of Egypt :

Numbers 26:4 Meaning and Commentary

Numbers 26:4

[Take the sum of the people], from twenty years old and upward,
&c.] At the same age at which the sum was taken before, ( Numbers 1:3 ) so that there could not be one that was more than sixty years of age, of all those that went into the land of Canaan, except Joshua and Caleb, and besides some few in the tribe of Levi, which did not come into either of these musters:

and the Lord commanded Moses, and the children of Israel, which went
forth out of the land of Egypt;
as Moses had a command to number the people before, so he had now. The sin of David was, that he numbered the people when he had no command for it; Moses, when he brought the people out of Egypt, had them committed to him by number; and now being about to die, he delivers them up as it were by number again, as Jarchi observes.

Numbers 26:4 In-Context

2 Take the sum of all the congregation of the children of Israel, from twenty years old and upward, according to the houses of their lineage, every one that goes forth to battle in Israel.
3 And Moses and Eleazar the priest spoke in Araboth of Moab at the Jordan by Jericho, saying,
4 from twenty years old and upward as the Lord commanded Moses. And the sons of Israel that came out of Egypt :
5 Ruben the first-born of Israel: and the sons of Ruben, Enoch, and the family of Enoch; to Phallu belongs the family of the Phalluites.
6 To Asron, the family of Asroni: to Charmi, the family of Charmi.

The Brenton translation of the Septuagint is in the public domain.