פירוש על במדבר 31:6

אתם ואת פינחס [MOSES SENT THEM … TO THE WAR], THEM AND PHINEAS — The repetition of the word אתם, “them”, in association with Phineas’ name tells us that Phineas was regarded as equal to all of them together. — But why did Phineas go and Eleazar did not go? The Holy One, blessed be He, said, “He who made a beginning with this meritorious work, in that he slew Kozbi the daughter of Zur (who was a Midianitess), let him complete it”. — Another explanation why Phineas and not Eleazar went is that he went to take vengeance for Joseph, his mother’s ancestor, as it is said, (Genesis 37:36) “And the Midianites sold him [unto Egypt]”. And from where do we know that Phineas’ mother was of the family of Joseph? Because it is said, (Exodus 6:25) that she was “one of the daughters of Putiel” (see Rashi on that verse) — which is explained to mean that she was of the seed of Jethro who used to fatten (פטם) calves for idolatrous worship, and of the seed of Joseph who overcame (שפטפט, who talked or argued with) his passions (cf. Sifrei Bamidbar 157:4; Sotah 43a). — Another explanation: Phineas went because he was the high priest anointed for war purposes (cf. Deuteronomy 20:2 and Rashi thereon) (Sotah 43a).

AND MOSES SENT THEM, A THOUSAND OF EVERY TRIBE. He did not send all the members of the army there, although the Midianites were a large people, and their cities were fortified, and very large.⁶⁴Ibid., 13:28. The reason for this is that those who had sinned with the Moabite women were many, and they were not fit to execute the vengeance of the Eternal;⁶⁵Verse 3. therefore they chose those men who were known amongst their tribes as righteous men.⁶⁶See Deuteronomy 1:13. Now Moses did not command them what to do, but merely told them to execute the vengeance of the Eternal on Midian,⁶⁵Verse 3. and he thought that they would let none of them remain or escape,⁶⁷Joshua 8:22. but [would execute the vengeance of the Eternal] like the vengeance [they were commanded] in connection with Amalek or the vengeance [they were commanded] in connection with the seven nations [of the land of Canaan]. And therefore when Moses saw that they had spared the women and children and the cattle, he was angry about [the fact that they had left alive] the women who had had sexual intercourse, because the officers of the army should have killed them as the very first thing, both as execution of the vengeance [which they were now commanded to do], and in performance of the general law of the Torah [that a living thing which causes a man to sin must be killed, as it is said], and ye shall slay the beast.⁶⁸Leviticus 20:15. And when he saw that the people wanted [to keep] the spoil, he remitted [and allowed them to keep] the female children⁶⁹Further, Verse 18. and the spoil.⁷⁰Ibid., Verse 20.
It is also possible to explain that Moses was [only] commanded to Harass the Midianites, and Avenge the children of Israel of the Midianites,⁷¹Above, 25:17, and Verse 2 of this Chapter. [but was not commanded to destroy them all like Amalek and the seven nations]. Therefore he sent only a small contingent [twelve thousand men] to strike at the unwalled towns⁷²Deuteronomy 3:5. and fell every good tree, and stop all fountains of water, and mar every good piece of land with stones⁷³II Kings 3:19. as spoilers usually do, and he did not give them any specific commands except that they should execute whatever vengeance they were able to do — and G-d, blessed be He, Who controls [the course of all] battles, gave the Midianites and their [five] kings and cities into their hands. Therefore Moses was only angry about [their sparing] the women who had had sexual intercourse, and [he was] not angry about anything else,⁷⁴Thus, according to this second explanation, Moses originally did not command them to destroy everything, but only to harass the Midianites as a form of vengeance. Hence we understand why he was not angry about their sparing the children and spoil, but only about their sparing the grown-up women who had caused the sin. and his command [to kill] the male children⁷⁵Verse 17. was an [additional measure of] retributive punishment.
Now Moses was wroth with the officers of the host⁷⁶Verse 14. but showed honor to Phinehas [by not criticizing him, too], because G-d had given unto him His covenant of peace.⁷⁷Above, 25:12. And in the Sifre we are taught:⁷⁸Sifre, Matoth 157. “Phinehas said to Moses: As you have commanded us, so have we done.” But I do not know what this statement means, since according to the Scriptural verses [here] Moses did not command them anything specific, for had he commanded them something which [as Phinehas said] they fulfilled, how could he [Moses] have been angry with them? [We cannot say that he was angry because they did not do everything that he told them to,] because had he commanded them, Heaven forbid that [we say that] Phinehas would transgress his command! Saul lost his kingdom on account of such disobedience!⁷⁹I Samuel 13:14. But the [explanation of the matter] is as I have said, that Moses [merely] commanded them to execute the vengeance of the Eternal on Midian,⁶⁵Verse 3. and Phinehas told him: “We have executed great vengeance on them.” It is also possible to explain that Phinehas told Moses: “Just as you charged us with the law of the Torah given at Mount Sinai, namely, When thou shalt besiege a city etc.⁸⁰Deuteronomy 20:19. In the context of Ramban’s remarks here, it would seem that the reference is to Verses 10-14 ibid: When thou drawest nigh unto a city to fight against it … but the women, and the little ones, and the cattle … thou shalt take. It was this law which was Phinehas’ defense. so have we done to them.” And Moses was angry about [their sparing] the adult women, because, Behold, these caused the children of Israel etc.,⁸¹Verse 16. and he added [the command to kill] every male among the little ones⁷⁵Verse 17. in order to complete the retribution.

וישלח אותם משה אלף אלף למטה לצבא, he sent one thousand men of each tribe.