Commentaire sur Les Nombres 1:45

AND ALL THOSE THAT WERE NUMBERED OF THE CHILDREN OF ISRAEL BY THEIR FATHERS’ HOUSES … ALL THAT WERE ABLE TO GO FORTH TO WAR IN ISRAEL. It was necessary for Scripture to state the collective number of the people although it had already stated the individual numbers [of each of the tribes], because Moses and Aaron were commanded to ascertain the total number of the people counted, as well as the number of [people in] each tribe, for such is the way of kings when they take a census of their people.
However I have not understood the reason for this commandment, namely why the Holy One, blessed be He, commanded [that they should ascertain the number of the people]. For whilst there was indeed a need for them [the people] to establish their relationship to the [individual] tribes because of the [division of the tribes of Israel according to four] standards, I cannot understand why G-d commanded that they find out the number [of men in each tribe]. Perhaps it was in order to proclaim His mercy over them, for it was with [only] threescore and ten persons that their fathers went down into Egypt,⁷³See Deuteronomy 10:22. and now they were as the sand of the sea, so many men [above] the age of twenty [not to mention the women and children]. After every epidemic and plague He counted them again in order that they should know that it is He that increaseth the nations;⁷⁴Job 12:23. He woundeth, and His hands make whole.⁷⁵Ibid., 5:18. It is for this reason that our Rabbis have said:⁷⁶Mentioned by Rashi, above. Verse 1; see also Bamidbar Rabbah 4:2. “Because of His abundant love for them He counts them every now and then.” Furthermore, he who comes before the father of the prophets, and his brother [Aaron] the holy one of the Eternal⁷⁷Psalms 106:16. and becomes known to them by name, receives thereby a merit and life, because he has come in the council of the people and in the register of the house of Israel,⁷⁸Ezekiel 13:9. The prophet Ezekiel states it in the negative as a punishment for sinners: they shall not be in the council of My people, neither shall they be written in the register of the house of Israel. Ramban, as indicated, applies it in the positive, namely, that those possessing merit will be included in the council of G-d’s people and be written in the register of the house of Israel. It is possible that Ramban also hints to the concluding part of that verse: neither shall they enter into the Land of Israel, thus intimating that those who are deserving of reward will enter into the Land. and he receives a part in the merits of the community by being included in their numbers. Similarly, each of the people receive a special merit through being counted by number before Moses and Aaron, for they will set their eyes upon them for good,⁷⁹Jeremiah 24:6. and intercede on their behalf for mercy, [just as it is said], The Eternal, the G-d of your fathers, make you a thousand times so many more as ye are,⁸⁰Deuteronomy 1:11. and He will not reduce your numbers, and the shekels shall be a redemption for your souls. And in Bamidbar Sinai Rabbah I have seen the following text:⁸¹I have not found the source thereof. “According to the number of names … by their polls.⁸²Verse 18 above. The Holy One, blessed be He, told Moses to count them each with respect and [to treat] each one of them with [the honor due to] greatness. [Thus He said]: You shall not say to the head of the family: ‘How many people are there in your family? How many sons do you have?’ but they are each to pass before you with awe and in respect, and you shall count them. — It is with reference to this that it is written, according to the number of names, from twenty years old and upward, by their polls. ”⁸²Verse 18 above.
It is also possible for us to say that [the reason for ascertaining their numbers] was similar to the practice of governments before fighting a war, since they were now ready to enter into the Land and to fight against the kings of the Amorite that were on the other side of the Jordan [eastward] and all the others, as Moses said [unto Hobab], We are journeying unto the place of which the Eternal said: This I will give unto you.⁸³Further, 10:29. Therefore Moses and the princes [of the tribes] had to know the number of those armed for war, and also the numbers of each and every tribe, [in order to decide] what to command each of them in the plains of Moab [when drawing up] the battle-lines, for the Torah does not rely on the miracle of one chasing a thousand.⁸⁴See Deuteronomy 32:30. This is the purport of the expression, all that go forth to the host in Israel,⁸⁵Above, Verse 3. namely that the census was for the purpose of [determining the number of] men that will go forth to war; and also so that he should distribute the Land to them according to their numbers, and should know how many parts will be allotted to them of the Land that they capture, since if not for the affair of the spies, they would have entered the Land immediately.

ויהיו כל פקודי....כל יוצאי בישראל צבא, none were over sixty years of age, as people of that age and beyond were not allowed to go out to war. We know this from Baba Batra 121 concerning Yair ben Menashe and others included in the count mentioned there. The decree that the generation of the spies would have to die in the desert applied only to the ones between 20-60. Those younger or older at the time of the spies’ trip were exempt from this decree.