John Calvin Commentary Numbers 31:25

"And Jehovah spake unto Moses, saying," — Numbers 31:25 (ASV)

And the Lord spake unto Moses. A most equitable distribution of the spoils is described here, in which the law of proportion was so well observed that, while the soldiers were not deprived of the reward for their labor, at the same time some advantage came to the rest of the people on whose behalf the war was waged.

The share of the multitude was indeed small, for the same proportion was awarded to the 12,000 as to the remaining 600,000. But, since the spoils had already been won by the soldiers by right of their victory, it should not have been a cause of complaint to the people who had not fought that they received an honorary gift, even if it was of little value.

And certainly, it would have been shameful for those who remained in the camp to be entirely without any share of the spoils, as if they had been convicted of cowardice, when in fact it was not their own doing that they had not joined their brothers in conquering the enemy.

For it was from no lack of courage that they had escaped the burden and the perils of war; rather, they had modestly allowed the general glory to be claimed by a few, because it had so pleased God. But, while it was just that some of the fruits of the victory should be shared with all, so it was no less right that the fuller and more liberal reward should be received by those who had borne the whole brunt of the war.

It appears to some that David followed the same rule when he distributed the spoils equally among his followers who had gone down to battle and those who had stayed with the baggage (1 Samuel 30:24).

In my opinion, however, what David then decided was very different. For if the portion of those who remained with the baggage had been equal to that of those who were actually engaged, it would have been far more advantageous to remain out of reach of the weapons. Indeed, when a battle is fought, only a few men out of a large army are generally left with the baggage, and thus half the spoils would have gone to a few idlers.

The division, therefore, which is mentioned there, must have been an equal distribution to each individual. And David very justly directed that those who remained stationed in the camp should have a full share of the spoils, so that²¹⁰ the condition of those who were operating under the same rule would not be different. But in this case, the actual warriors are justly rewarded above those who quietly attended to their own domestic concerns.

²¹⁰ The Fr. gives a different turn to the sentence, “veu que tous a la verite guerroyoyent;” seeing that in truth all were alike engaged in the war.