Charles Ellicott Commentary Numbers 1:16

"These are they that were called of the congregation, the princes of the tribes of their fathers; they were the heads of the thousands of Israel." — Numbers 1:16 (ASV)

The renowned of the congregation. — Literally, the called men of the congregation, that is, the men chosen as representatives of their respective tribes and appointed to act in that capacity in regulating the affairs of the nation.

Heads of thousands in Israel. — Better, they were the heads of the thousands of Israel. Compare Exodus 18:21; Exodus 18:25, where rulers, or princes of thousands, are the highest class of officers recommended by Jethro and appointed by Moses. See also Numbers 10:4.