What is "la'Eileh Techalek ha'Aretz" coming to teach us?
Rashi: It teaches us that only those who were twenty at that time received a portion in Eretz Yisrael, to prelude whoever was not yet twenty - even if they would turn twenty before they distributed the land. 1
Targum Yonasan: It teaches us that Eretz Yisrael was divided among the tribes (into twelve unequal portions) 2 - and not among the individual people (into six hundred and one thousand ... portions).
Bava Basra, 17a: It precludes children ? who were under twenty when they left Egypt - from receiving a portion. 3
Oznayim la'Torah: Based on the fact that the Torah inserts the words "be'Mispar Sheimos", it teaches us, either that the above-mentioned would inheritit the land, but purely according to the Yotz'ei Mitzrayim listed in Bamidbar - where the Torah used the Lashon "be'Mispar Sheimos 4 - or that the aforementioned would inherit the land according to the current list, but in conjunction with the list in Bamidbar. 5
Rashi: Which they began doing seven years later, when they finished conquering it. In other words, the land was divided into six hundred and one, seven hundred and thirty portions, and even someone listed here who had six children received only one portion ? like R. Yonasan, who maintains that the land was divided according to those who entered it (Sifsei Chachamim).
Targum Yonasan (in Pasuk 54): According to the size of the tribe.
See Torh Temimah, note 6.
Oznayim la'Torah: According to those who hold that the land was divided according to Yotz'ei Mitzrayim exclusively,;
What are the connotations of "be'Mispar Sheimos"?
Ramban (in Pasuk 54) 1 : It means that the land is to be divided among the above-mentioned families; 2 that each individual male should receive his portion - a larger family received more, a small family, less. Consequently, when the territory of Reuven was divided into four parts, the larger family of Chanoch (assuming that it was indeed larger) received a bigger portion, whereas that of the smaller family of Palu, a smaller one ? because each family received its portion according to the numbers of its members. 3
QUESTIONS ON RASHI
Rashi writes that if one had six sons, they received only one share (of their father). What is the case?
Riva: Rashi explains according to the opinion that the land was divided among those who left Egypt. If one [who left] had six sons [who entered], they received only one portion. Later, Rashi explains like the opinion that it was divided among those who entered Eretz Yisrael. 1
Mizrachi: Rashi explains according to the opinion that the land was divided among those who entered the land. (If one who entered had six sons less than twenty, they received only one portion).
Also the first part of this Rashi implies that it was divided among those who entered, for he said 'this excludes men who turned twenty after entering the land!' Perhaps it means that those who left bequeathed only to sons (and grandsons?) who were at least twenty when they entered. Perhaps Riva did not want to explain that it was divided among those who entered, for after Rashi said that those less than 20 did not receive, it is no Chidush that if one had six sons less than twenty, they received only one share. (PF)