Here is a response by Rabbi Micha Golshevsky to my post, questioning how Yishmael could have been disinherited just by being driven out of Avraham's home. Thank you Rabbi Golshevsky!
In the course of my research for my piece in Daf Digest a short time ago I ran into several answers to your question.
Perhaps the simplest answer is that of the Be'er Sheva (in Sanhedrin [91a] D"H: ul'vnei hapilagshim). He explains that since Yishmael was a shifcha's son, he was not considered Avraham's son and could not inherit for this reason. The Ohalei Yitzchak asks a question on this Be'er Sheva. He asserts that this seems very unlikely since it seems clear to him that any child of Avraham was b'kedushah (conceived of a "converted," Jewish mother). How could she have not converted all the way either before she was expecting or after?
However, I am not sure what indication there is that Yishmael was indeed born b'kedusha, unlike the Ohalei Yitzchak assumes. Because Sarah told Avraham to marry Hagar for her own benifit, what proof is there that it was b'kedusha? After all, Sarah treated her as a shifcha even after Hagar was expecting!
Furthermore, see the Rambam in Nachalos 6, 9. Although the gemara in Kiddushin 17 mentions that a non Jew inherits min HaTorah, the seder of yerushah does not apply to a non Jew at all.
Although Yishmael was Avraham's son, he was born from a shifchah. Even if he is considered b'kedushah in some way, who is to say that if he leaves he doesn't forfeit his rights. It is plausable that a child of the avos born from a shifcha is Jewish and inherits only if he is treated as a child. If he is evicted he does not.
It is also possible that Sarah didn't mean from a halachic point of view. After all, when Avraham sent Eliezer to find a wife for Yitzchak, the Midrash (Breishis Rabbah Parshah 59 siman 11, brought in Rashi) records that he carried with him a document declaring all of Avraham's property to Yitzchak. Maybe this is what Sara meant.
Machaneh Yehudah (siman 282) explains that Avaraham was unsure about Yishmael since he didn't know if a very righteous person would come out of his descendants and make giving him the inheritance worthwhile. Sarah, who was much greater than Avaraham in prophecy, saw that there would not be any such righteous descendants. Maybe he means the second answer above (although he may mean the first or a different answer.
The truth is that the way I saw this whole discussion was from the other side: It is clear that Avraham removed any inheritance from Yishmael with the above document. The Mizrachi asks: how could Avraham avinu avoid Yishmael receiving any inheritance? After all, he fulfilled the entire Torah and in Kesuvso 53 we find that one should not tamper with his inheritance even to give his "good" son and remove from his "bad" son. It is in this context that the sources brought here discuss this issue.
I honestly did not have a problem with this question since bad in the gemara (that prohibits disinheriting a bad child) need not mean an idolater, just a less good human being for whatever reason. Chazal prohibited us to give the money to the better one, because of what may come out of the bad. But Yishmael was an idolater. The Maharam Shick (Choshen Mishpat, siman 43)writes that this rule only applies to someone who either doesn't treat his parents properly (Rambam) or isn't exactly perfect in his obligations to heaven (Tur) Not an idolater etc.
The Sadei Chemed and the Igros Moshe (Choshen Mishpat II siman 50) both concur with this psak so the Mizrachi's problem doesn't begin. Of course the Mizrachi clearly argues but the other luminaries may be explaining according to his understanding even if they would agree with the Maharam Shick etc in principle.
-Rabbi Micha Golshevsky
(Picture courtesy of middleeasternparent)
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