What did Yaakov mean when he added that 'progeny born to you after them will be called on the name of their brothers in their inheritance'?
Rashi, Ramban #1 (to 48:15, citing Onkelos) 1 : Any children that Yosef will bear from now on, 2 will no longer be counted among his (Yaakov's) children, but will join the tribe of Efrayim or of Menasheh.
Seforno: From now on, Menasheh's children will belong to the tribe of Menasheh and those of Efrayim will belong to Efrayim.
Ramban #2 (to 48:15): It means that the children that were born to Yosef after Yaakov arrived in Egypt 3 would join either the Tribe of Efrayim or that of Menasheh.
Peninim mi'Shulchan ha'Gra: If a child died, the next child born should be called like his dead brother, with a new name added beforehand. 4
Ohr ha'Chayim, Malbim: Only Efrayim and Menasheh will be counted among the tribes, but any subsequent sons of Yosef will not count as a third tribe.
Malbim: Eretz Yisrael was given to Yaakov, and afterwards to his seed (refer to 48:4:152:1). It was considered his, for Kedushas Eretz Yisrael to take effect on it, only as long as he was in Eretz Yisrael. Once he left, his rights passed to his sons. Efrayim and Menasheh merited [to become two Shevatim] via Yaakov when he was still in Eretz Yisrael, but sons that will be born from now and onwards cannot merit.
Who translates "Asher Holadta... " in the future.
Rashbam: The same applies to grandchildren, or children born after Yaakov arrived in Egypt. Ramban - Yaakov would not have made a vain statement. If he referred to children that would still be born to Yosef, it must have come true. (Also refer to 48:6:1.3.)
As implied both in this Pasuk and in the previous one, as well as in Miketz (41:50 [Ramban]).
This is based on the Zohar. It helped the Gra's grandchildren and many others.
How did Yaakov know that Efrayim and Menasheh will be in place of Yosef, and not in addition to his own portion? And how did he know that Yosef's sons will be separate Shevatim, and not other grandsons, e.g. Yehudah's sons Peretz and Zerach, who were greater (in that kings would come from them)!
Ohr ha'Chayim: The Zohar says that Yosef is the aspect of Nefesh Yaakov - "Eleh Toledos Yaakov, Yosef" (37:2); "Bnei Yaakov v'Yosef" (Tehilim 77:16). Also Yosef is a father of Shevatim. The promise that Yaakov will father more Shevatim is fulfilled via Yosef. Yosef's children are at the level of Reuven and Shimon (Yaakov's children). Yosef is not counted with his sons [as a Shevet], just like Yaakov is not.
Why does it say "Yikare'u b'Nachalasam"?
Ha'amek Davar: Only regarding inheritance they are called on their brothers' names, but otherwise, Yosef's honor is not diminished. Several times it says "Mateh Yosef."
QUESTIONS ON RASHI
Rashi writes: "'Your offspring [which you fathered after them]' - [I.e.] if you shall father more children...." The verse is in past tense; why does Rashi change it to future tense?
Gur Aryeh: If Yosef already had other children in the interim, why didn't he bring them along as well, to receive Yaakov's blessing? It must be that Yosef did not as of yet have more sons.
Rashi writes: "'Your offspring [which you fathered]' - [I.e.] if you shall father more children...." If Yosef did not yet have more sons (refer to 48:6:1.1:1), why does Yaakov speak in past tense?
Gur Aryeh: Yaakov knew with Ru'ach ha'Kodesh that just as Yosef had not yet fathered any additional sons, he would not have more sons in the future either. 1
Gur Aryeh: If Yaakov knew this, why didn't he tell Yosef explicitly? That would sound like Yosef didn't merit a share in the Land in his own right, only indirectly through his sons. On the contrary, Efrayim and Menasheh received Yosef's portion - as we see that even future sons of Yosef could [theoretically] join that share.
Rashi writes: "If you shall father more children...." Why does the Torah record this? We do not know of any more children born to Yosef!
Gur Aryeh #1: Perhaps Yosef would indeed have more children. They are not mentioned because they are included in the tribes of Efrayim and Menasheh, as per this verse.
Gur Aryeh #2: Based on the preceding verse (48:5), Yosef might likely think that any future sons of his would become Shevatim as well. He could take another wife, 1 and father more children! Yaakov had to specify that even if Yosef were to do so, they would be included under their brothers Efrayim and Menasheh.
Gur Aryeh #3: Yosef might likely think that while Efrayim and Menasheh would each be Shevatim in their own right, Yosef also retained his own status as a Shevet. He could pass on that status to any sons born to him in the future; and if none would be born, he would pass it on to Efrayim and Menasheh (for a total of three portions in the Land). Yaakov therefore specifies that Yosef would not retain his own portion.
Rashi writes: "... Although the Land would be divided per person (Bamidbar 26:54), [such that] each person would receive an equal share... "(and if so, what advantage did Efrayim and Menasheh have over future sons of Yosef?). Ramban asks - According to the Gemara's conclusion (Bava Basra 121b-122a), the Land was [first] divided up among the number of tribes! If so, there was great advantage in being called a tribe!
Gur Aryeh (to 48:5) #1: To Rashi, that Gemara is asking whether lots were used for the tribal portions, or for each person's individual portion (but in either case, the size of the tribal portions would be proportional to their numbers.) The Gemara concludes that the lots were for the tribal portions. (Menasheh and Efrayim's advantage was only in that they had their own Nasi, who would draw a lot on their behalf.)
Gur Aryeh (to 48:5) #2: Alternatively (unlike Rashi), the lots were among the tribes, and the Gemara is asking whether the twelve tribal portions were all equivalent, or of various sizes in accordance with the tribes' various populations. 1 Efrayim and Menasheh would be individual tribes in this lottery, and this was to their great advantage.
For a thorough discussion of how Eretz Yisrael was divided among the tribes, see "Erkah Shel Eretz Yisrael" by Rabbi Yehudah Landy, Chapters 13 and 16.
Rashi writes: "... Although the Land would be divided per person (Bamidbar 26:54), [such that] each person would receive an equal share..." (and if so, what advantage did Efrayim and Menasheh have over future sons of Yosef?). Mizrachi asks - Perhaps [we need this Pasuk because were it not so,] any future sons of Yosef would not receive a share in the Land at all?
Gur Aryeh #1: It is clear that the Pasuk is coming to give Menasheh and Efrayim an advantage over the other tribes; 1 not to put other sons of Yosef at a disadvantage [to everyone else].
Gur Aryeh #2: Why would other sons of Yosef be disqualified from a share in the Land? Whether the Land was divided among those who left Mitzrayim, or [their sons] who arrived in the Land, 2 they would qualify just as all the rest of Bnei Yisrael.
Rashi writes: "... Nevertheless, [their advantage was that] only they (Efrayim and Menasheh) would be called tribes." What was their advantage in the practical sense?
Gur Aryeh: Refer to 48:5:0.3.
