QUESTIONS: The Gemara teaches an important principle with regard to providing merit for one's father or for one's son. The Gemara says that a son can bring merit to his father, but a father cannot bring merit to his son. For this reason, Avraham Avinu will not be able to save Yishmael from Gehinom, and Yitzchak will not be able to save Esav from Gehinom.
There are several questions on this Gemara.
(a) How can the Gemara here say that the merits of a father do not protect his children, when the Gemara in Yoma (87a) states the opposite? The Gemara there states that not only do the actions of a Tzadik protect the Tzadik himself, but they also provide merit for his children and grandchildren for all generations. (GILYONEI HA'SHAS)
Similarly, the Gemara in Berachos (6a) teaches that when a Rasha is seen to be living a comfortable life, it is because he is the son of a Tzadik. In fact, the Torah itself teaches that the merits of a person last for a thousand generations (Devarim 7:9, see Sotah 31a). It is a common theme that the Jewish people have Zechus Avos from the forefathers that protect them forever (Berachos 27b, Shabbos 55a).
(b) The Gemara implies that Yishmael died as a Rasha. This is also the implication of the Gemara in Megilah (17a, and RASHI there, DH Lamah Nimnu) and the Midrash (Bereishis Rabah, end of Chayei Sarah), which ask why the Torah counts the years of Yishmael if he was a Rasha. However, the Gemara in Bava Basra (16b) quotes Rebbi Yochanan who derives from the verse (Bereishis 25:17) that Yishmael repented during his father's lifetime. When the verse describes Yishmael's death, it says "va'Yigva va'Yamas," a phrase used only to describe the death of Tzadikim. It should not be necessary, therefore, for Avraham Avinu to have to save him, since Yishmael should deserve Olam ha'Ba based on his own merits!
Another proof that Yishmael repented may be derived from the fact that a Tana has the name Rebbi Yishmael. If Yishmael died as a Rasha, the use of his name would be prohibited, as the Gemara says in Yoma (38b; see Tosfos there with regard to the names "Avshalom" and "Shavna"). (TOSFOS YESHANIM to Yoma 38b, cited by GILYON HA'SHAS; TORAS CHAIM, TUREI EVEN, and MAHARSHA to Megilah 17a.)
(a) The RIF in the EIN YAKOV explains that the merit of a father can help the son while the son is alive in this world. As long as the son is alive, the father's merit can grant him a comfortable life so that it will be easier for him to repent and do Mitzvos. This is the way in which Zechus Avos protects a person.
However, after the son has died and no longer can perform Mitzvos, the Mitzvos that his father did cannot grant the son a share of eternal reward which he does not deserve. This might also be the intention of TOSFOS in Sotah (10b, DH d'Ayesei). Tosfos there asks how David ha'Melech was able to save his son Avshalom from Gehinom through his prayers, if the merits of a father do not help the son. Tosfos answers (in his first answer) that since Avshalom suffered in this world by enduring a terrible death, his father's prayers were able to bring him to Olam ha'Ba. This might be based on the assumption, mentioned above, that while Avshalom was alive the merit of his father brought about his tragic death in order that his death could serve as an atonement for him when his father would later pray for him.
(b) The TOSFOS YESHANIM in Yoma explains that although the Gemara here and in Megilah (as well as the Midrash in Bereishis Rabah 62) calls Yishmael a Rasha, the Gemara in Bava Basra disagrees with the Gemara here and in Megilah and maintains that Yishmael was not a Rasha.
Why, according to the Gemara here and in Megilah, did a Tana bear the name of Yishmael if Yishmael was a Rasha? The Tosfos Yeshanim answers that since it was Hash-m Who gave the name Yishmael to the son of Hagar when he was born (Bereishis 16:11), it is permitted to use that name despite the fact that its original bearer was wicked.
RASHI, however, apparently understands that the Gemara in Bava Basra agrees with the Gemara here and in Megilah. Rashi (to Bereishis 25:17) first cites the Gemara in Megilah, which says that the Torah lists the number of years Yishmael lived in order to teach the amount of time Yakov spent in the Yeshiva of Ever. Rashi then proceeds to cite the Gemara in Bava Basra, which derives from the expression "va'Yigva va'Yamas" that Yishmael repented before his death. (In fact, the only other places in which this phrase is used is with regard to the Avos themselves -- Avraham (Bereishis 25:8), Yitzchak (Bereishis 35:29), and Yakov (Bereishis 49:33), implying that it indeed refers to a Tzadik's death.) When the Midrash says that the Torah should not have listed the years of Yishmael because he was a Rasha, the MAHARSHA (in Megilah) and the MAHARAL (in Gur Aryeh) explain that the Midrash means that since Yishmael was not righteous all of his years, they should not have been listed. However, Yishmael indeed died a Tzadik, as the Torah refers to his death with the terms "va'Yigva va'Yamas."
Why, then, does the Gemara here assert that Yishmael died a Rasha, and that the only thing that would have saved him from the fate that he deserved was the merits of his father?
1. The ETZ YOSEF in the Ein Yakov suggests that the Gemara here is not referring to Yishmael himself. It is referring to his offspring (who are referred to collectively as "Yishmael"). Avraham cannot save the evil offspring of Yishmael from Gehinom, since a father does not bring merit to his son (after the son's death).
2. The YAD DAVID answers based on the words of Tosfos (Yoma 38b, Shabbos 12b). He says that Rebbi Yishmael was named after a different Yishmael who was a Tzadik. (A different Yishmael indeed is mentioned in Ezra 10:22; he may well have been a Tzadik.)
3. Perhaps the Gemara in Bava Basra does not mean that Yishmael died as a Tzadik. The Gemara there says only that he repented before the death of Avraham Avinu. This occurred in order to fulfill the promise Hash-m made to Avraham that he would see Yishmael do Teshuvah and live a productive life (Rashi to Bereishis 17:18). The Gemara in Bava Basra says that this was the blessing that the Torah refers to as "ba'Kol" (Bereishis 24:1). After Avraham Avinu died, however, Yishmael sinned again, and he died as a sinner. That is why the Gemara here says that Avraham Avinu's merit cannot bring Yishmael to Olam ha'Ba.
Support for this answer is found in Rashi (to Bereishis 25:18) who writes that until Avraham Avinu died, Yishmael lived in a respectful manner. After Avraham Avinu died, Yishmael "fell" (as mentioned in Bereishis 25:18), implying that he returned to his sinful ways (see KLI YAKAR there).
Why, then, does the verse use the phrase "va'Yigva va'Yamas" to describe Yishmael's death? The answer is that the RAMBAN (to Bereishis 25:8) explains that when "va'Yigva" is written with the word "va'Ye'asef," it implies the swift death of "Neshikah" with which Tzadikim die. Perhaps Avraham Avinu's prayer was not only that he should see Yishmael return to the ways of righteousness in his lifetime, but that if Yishmael does repent he should be judged favorably in this world and live in peace and die the death of a Tzadik. Afterwards, however, Yishmael returned to his evil ways of his own free choice, despite the Heavenly assistance he would have had to remain righteous (see Ramban and Maharal to Bereishis 17:18). However, Hash-m promised that Yishmael would continue to live without want and would die painlessly -- like the Avos themselves. (He would receive punishment for his evil ways not in this world but in the World to Come.) Therefore, despite Yishmael's return to his old ways, he died the form of death normally reserved for Tzadikim. This may be what Rashi means (in Bereishis 25:17) when he writes with regard to Yishmael that "the wording used in this verse is the wording reserved normally for Tzadikim" -- not that Yishmael himself died a Tzadik.
However, had Yishmael never acted in a righteous manner, Hash-m would not have granted him the death of a Tzadik, since it is obvious that Hash-m's promise to Avraham was contingent upon Yishmael's Teshuvah (at some point). This is how the Gemara in Bava Basra (16b) proves from the word "va'Yigva" that Yishmael must have repented at least at one point in his life. (M. KORNFELD)