Midrash sobre Números 31:40

...If the house is too small [to be for a lamb] - it teaches that they may decrease themselves in number continuously, provided that one from the fellowship remains, those are the words of R. Yehudah. Rabbi Yosi says: whether from the first or second fellowships, and provided that they do not leave behind any quantity of the Passover [sacrifice], the text says: '[being] for a lamb' - that is, [for maintaining it alive] for eating, and not for acquiring. Rabbi [Yehudah HaNasi] says: even for acquiring since if he does not have, he appoints others for his place, and [selects] coins for non-holy [purposes] that were taken at the outset only for this. "And he will take" - this teaches that each and every fellowship takes for itself, from here they said 'we do not slaughter the Passover [sacrifice] for an individual from the outset, as it is written "You are not to slaughter the Passover [sacrifice] in/for one (Deuteronomy 16:5), these are the words of Rabbi Yehudah. Rabbi Yosi says: there are moments when he is only one, and we do slaughter for him, there are times when they are ten and we do not slaughter for them. How is it possible? If he is one, and is able to eat it all, we slaughter it for him; ten, and they cannot eat it all, we do not slaughter for them so that they won't invalidate the Passover [sacrifice]. "And his neighbor" - Ben Bag Bag says: [from this] I only understand [lit. hear] his neighbor in the fields, from where [do I derive] his neighbor under the same roofs? The text says "close to his house": door [next] to door. Rabbi [Yehudah HaNasi] says - three are spoken of: 'his neighbor' - this is his neighbor in the fields; 'and his neighbor' - this is his neighbor under the roof; 'close' this is the neighbor close to his house, next to the door. [In] The Egyptian Passover his neighbor [was] close to his house, and in the Passover for the other generations, his neighbor is not close to his house. Rabbi Shimeon says: Even in the Passover for the generations his neighbor is [defined as] close to his house, and the Torah only said this due to the ways of peace, so that a person would not settle one's friends, and one's close neighbors, and one's acquaintances, and one's more distant acquaintances, and one of the dwellers of his town, and then goes and does his Passover with other people so as to fulfill what is written: 'a close neighbor is better than a distant brother' (Ecclesiastes 27:10). "In proportion" [quota] - the only 'proportion' is a minian, and so He says "and the quota [levy] for Ad-nai thirty two people [lit. souls]' (Numbers 31:30). Is it possible that it is a mitzvah to slaughter to his minian and if he did not slaughter it to his minian he transgressed but it is still kosher? (No,) the text says "proportion" "you shall apportion" - the text teaches regarding him that (if he does this) it is pasul (contrary of kosher). From the fact that the text states "man" I only a male, from where do we include women and minors? The text says "persons [lit. souls]". If that is the case, why does the text say "man"? Just as a man is able to eat an olive size (of the sacrifice) so too a minor [is only considered a minor] if he is able to eat an olive size (of the sacrifice). Rabbi Yehudah says: 'just as a man knows to differentiate food, so too a minor (is only considered a minor) if he is able to differentiate food. And what is to differentiate food? Anyone to whom we give an egg and s/he keeps it; a stone, and s/he throws it. "Proportion" "you shall apportion" - this teaches that we are counted and we count for the minian. From here they said 'the participants in a fellowship that counted others for their portion, have the permission to do so. If they want to continue and count others in their portion, they have the permission to do so. One of the participants in a fellowship that counted another person for his portion, he has the permission to do so. If he wants to continue and count others in his portion, he has the permission to do so. "According to what each will eat" - this excludes a person who is sick, an uncircumcised and one whose ritual status is 'impure'. "On the lamb" - Ben Bag Bag says: I understand [lit. I hear] a live lamb or a slaughtered one, you make the decision. Here (v.4) it says "a lamb" and there it says "a lamb" (v.3), just as the lamb said there is alive and not slaughtered, here, too, it is alive. From here they said 'we always apportion according to the Passover sacrifice, and we prevent [lit. hold their hands back] them (from apportioning) until it is slaughtered.