Jamieson-Fausset-Brown on Numbers 31:5
there were delivered--that is, drafted, chosen, an equal amount from each tribe, to prevent the outbreak of mutual jealousy or strife. Considering the numerical force of the enemy, this was a small quota to furnish. But the design was to exercise their faith and animate them to the approaching invasion of Canaan.
John Gill on Numbers 31:5
So they were delivered out of the thousands of Israel,.... Several thousands very probably offered themselves voluntarily to go to the war, or however were summoned together on this account, and out of them the following number was delivered of picked and chosen men:
a thousand of every tribe, twelve thousand armed for war; which was but a small number to go against so considerable a nation and people; but this was done to show that the war was of the Lord, he would fight the battle, and give them victory, it being the same to him to do it with few as with many; and to encourage the people of Israel to believe the Lord would give them success against their many and powerful enemies in the l…
Read the whole note in the consoleJohn Calvin on Numbers 31:3-6
And Moses spake unto the people. There is no doubt but that Moses delivered the commands which he had received from God; although, therefore, it is stated [205] that only ten thousand went forth to the war, yet the facts themselves demonstrate that the number, as well as the mode of warfare, was prescribed by God. And assuredly it would have been inconsiderate of Moses to attack so great a people with so small a band; and thus he would have deservedly incurred the penalty of his rashness, if he had attempted it of his own accord; still, when God's command had preceded, he happily concluded the matter, which had been properly and rightly undertaken. Nor can it be questioned but that God desir…
Read the whole note in the consoleKeil & Delitzsch on Numbers 31:3-6
To carry out this revenge, Moses had 1000 men of each tribe delivered (ימּסרוּ, see at Num 31:16) from the families (alaphim, see Num 1:16) of the tribes, and equipped for war; and these he sent to the army (into the war) along with Phinehas the son of Eleazar the high priest, who carried the holy vessels, viz., the alarm-trumpets, in his hand. Phinehas was attached to the army, not as the leader of the soldiers, but as the high priest with the holy trumpets (Num 10:9), because the war was a holy war of the congregation against the enemies of themselves and their God. Phinehas had so distinguished himself by the zeal which he had displayed against the idolaters (Num 25:7), that it was imposs…