by the commandment of the LORD. Compare Deuteronomy 1:19-22.
commandment. Hebrew "mouth". Figure of speech Metonymy (of Cause), App-6, put for what is spoken by the mouth.
heads. captains over thousands. Exodus 18:25.
Related Commentaries of Numbers 13:3
Numbers 13:3
3 And Moses by the commandment of the LORD sent them from the wilderness of Paran: all those men were heads of the children of Israel.