1) THE WORRIES OF TZADIKIM
QUESTION: The Gemara quotes Rebbi Yanai who instructed his sons before he died, "My sons, do not bury me in black clothes or in white clothes. [Do not bury me in] black clothes, because I might merit [Gan Eden], and [if I am wearing black clothes] I will be like a mourner among grooms. [Do not bury me in] white clothes, because I might not merit, and I will be like a groom among mourners. Rather, bury me in crimson clothes that comes from across the sea."
A similar doubt about one's fate in the World to Come was expressed by Rebbi Yochanan ben Zakai in Berachos (28b). On his deathbed, he proclaimed to his students, "There are two paths in front of me, one of Gan Eden and one of Gehinom, and I am unsure on which one they will lead me!"
How is it possible that these great Tzadikim had any doubt that they might descend to Gehinom after their deaths?
ANSWERS:
(a) The ETZ YOSEF here writes that Tzadikim often are concerned that they might have committed a small transgression, such as a sin of wrongful speech or wrongful thought, that will require them to undergo Gehinom to atone for their sin before they go to Gan Eden, since Hash-m is very stringent with Tzadikim (Bava Kama 50a). Just as Moshe Rabeinu was unable to enter Eretz Yisrael because of his small transgression of hitting the rock instead of speaking to it, a Talmid Chacham may be held accountable for a small sin that will require a brief sojourn in Gehinom. This also may have been the meaning behind the proclamation of Rebbi Yochanan ben Zakai. (This explanation seems to be the intent of RASHI (DH Shema Ezkeh) as well.)
(b) The RAMA MI'PANO (in ASARAH MA'AMAROS, Ma'amar Chikur ha'Din 3:2) gives a different explanation for the Gemara in Berachos. After he asks how such great Tzadikim could have been worried about their fate in the World to Come, he says that Rebbi Yochanan ben Zakai knew that he was going to Gan Eden. However, there are two ways to get to Gan Eden. One is by taking a pleasant, direct path straight there, and another is by taking an indirect path through Gehinom. He explains that the latter route is actually a way for Tzadikim to achieve atonement for wrongful thoughts they might have had while in this world, without the need for an extended stay in Gehinom. In addition, along the way they are able to save certain Resha'im from Gehinom. However, merely passing through Gehinom is also an immensely frightening experience, and Rebbi Yochanan ben Zakai was worried that this might be the path to Gan Eden that he would have to take.
We may apply the Rama mi'Pano's explanation of the Gemara in Berachos to the Gemara here as well. Rebbi Yanai meant that although he knew that he will merit Gan Eden, he was unsure about how he should be buried. If he would be buried in black clothes and take the path that does not go through Gehinom, then he would be like a mourner among grooms, since he would have had no reason to be dressed in black. If he would be buried in white clothes and take the path that goes through Gehinom, then he would be like a groom among mourners, since he would be passing through Gehinom and mingling with the Resha'im there. (Y. MONTROSE)
2) BLACK LIKE A RAVEN
QUESTION: The Gemara concludes that a bloodstain the color of black ink is Tamei. The Gemara also concludes that if the stain is the color of a raven, it is Tahor. This implies that a raven is lighter in color than black ink.
In the laws of Tefilin, the BI'UR HALACHAH (OC 32, DH Yichtevem) asks that the Halachah requires that black ink be used for Tefilin. Any other shade of ink is invalid. However, the Midrash states that the words, "Shechoros k'Orev" -- "Black like a raven" (Shir ha'Shirim 5:11), refer to the letters of a Sefer Torah. If raven-black is a shade lighter than black ink, then a Sefer Torah with letters "black like a raven" should be invalid!
ANSWER: The BI'UR HALACHAH suggests that according to the Gemara's conclusion, dry ink is darker than wet ink. Therefore, a bloodstain must be compared against dry ink. The Midrash, in contrast, is teaching that when the letters of the Sefer Torah are still wet, they are black like a raven.

20b----------------------------------------20b

3) HALACHAH: DECIDING HALACHIC QUESTIONS FOR ONESELF
QUESTION: The Gemara relates that Rav Nachman's wife, Yalta, showed her bloodstains to Rabah bar bar Chanah and to Rav Yitzchak brei d'Rav Yehudah.
Why did she not show her bloodstains to her own husband, Rav Nachman, for a Halachic ruling? Rav Nachman was a great Talmid Chacham and a Gadol ha'Dor (see Sanhedrin 6a). Why did Yalta find it necessary to bring her Mar'os to someone else for a ruling?
Perhaps the reason why she did not show her Mar'os to her husband is that a Chacham is not allowed to rule on matters that directly affect him. The Mishnah in Nega'im (2:5) states, "A Chacham may rule on all Bechoros except for his own. However, he may rule even on his own Korbanos, Ma'asros, and Taharos." The Gemara in Bechoros (31a; see Insights there) explains that a person may rule on his own Taharos because there is no real difference to him whether they are Tahor or Tamei; even if he finds them to be Tamei he may eat them while he is Tamei. However, a person should be allowed to rule for himself only on the Taharah of his Chulin. In the case of a doubt regarding Isur v'Heter (such as Mar'os of his wife), he should not be permitted to rule for himself.
However, the Gemara in Eruvin (63a) clearly permits a Talmid Chacham to rule for himself even in such matters. Why, then, did Yalta not bring her questions to her husband, Rav Nachman?
ANSWERS:
(a) The RASH (Nega'im 2:5) answers that a Chacham is allowed to rule for himself in any case of Isur v'Heter that is not "Ischazek Isura" (presumed to be forbidden until now). When the object in question is Ischazek Isura, he may not rule for himself. (See also PISKEI TOSFOS (Bechoros #72) who writes that a person is trusted to rule for himself in all cases of Isur v'Heter.)
TOSFOS here (DH Kol) writes that a husband may certainly rule on the bloodstains of his wife. Yalta did not show them to Rav Nachman for other reasons (perhaps the other Poskim were more experienced in the laws of stains, or perhaps Rav Nachman was exceedingly stringent when his rulings affected himself, or perhaps Yalta was embarrassed). The SHACH (YD 188:7) cites the words of Tosfos and rules that a husband may rule on his wife's Mar'os.
(b) The MAHARACH OR ZARU'A (Teshuvos #97) adds that the Torah explicitly teaches that a Nidah is trusted to count the necessary days of Tum'ah on her own (see Kesuvos 72a). This law implies that a Chacham, too, is trusted to rule for himself with regard to the laws of Nidah.
(c) However, the ME'IRI here maintains that a husband may not rule on the stains of his wife, and that is why Yalta did not show them to her husband even though he certainly was a qualified Posek.
The MANOS HA'LEVI and BEN YEHOYADA in Megilah (13b) similarly write that although a husband is permitted to rule on his wife's Mar'os, it is improper for him to do so. They point out that this approach explains a seemingly problematic Gemara in Megilah (13b). The Gemara derives from the verse, "And Esther carried out the word of Mordechai" (Esther 2:20), that Esther would show her Nidah questions to the Chachamim. Why does the Gemara need to point out that Esther brought her Nidah questions to the Chachamim? All Jewish women are required to bring such questions to the Chachamim! The Gemara must be teaching that Mordechai told her to show her questions to the Chachamim and not to himself, since it is improper for a husband to rule on the Nidah questions of his own wife (Y. MONTROSE). (This approach does not appear to be accepted as the Halachah.)
4) HALACHAH: SEEKING A SECOND OPINION
QUESTION: The Gemara relates that Rav Nachman's wife, Yalta, showed a Mar'eh of Dam to Rabah bar bar Chanah, and he ruled that it was Tamei. She then took it to Rav Yitzchak brei d'Rav Yehudah, who ruled that it was Tahor. The Gemara asks how Rav Yitzchak was permitted to rule that it was Tahor when Rabah bar bar Chanah already ruled that it was Tamei. A Beraisa says that a Chacham is not allowed to issue a contradictory ruling once another Chacham has already ruled on the question. The Gemara explains that Rav Yitzchak initially ruled that it was Tamei as well, but when Yalta explained that Rabah bar bar Chanah was always lenient with such a Mar'eh but today his eyes were sore, Rav Yitzchak reassessed the question and ruled that it was Tahor.
However, the Gemara in Avodah Zarah (7a) rules that when a person brings a question to a Chacham and he rules stringently, then the questioner is not permitted to ask another Chacham the same question in order to receive a lenient answer. Why was Yalta permitted to ask Rav Yitzchak to rule on the Mar'eh once Rabah bar bar Chanah already ruled stringently?
ANSWER: TOSFOS (DH a'Gemarei) explains that it is prohibited only for the second Chacham to contradict the ruling of the first Chacham. However, it is not prohibited for the questioner to ask again, since the second Chacham might point out some factor or mistake that the first one overlooked, and the first Chacham will change his ruling. Tosfos notes, however, that the one asking the question is required to inform the second Chacham that he has already asked his question to another Chacham.
This, however, explains only why it was permitted for Yalta to ask her question. Why was it permitted for Rav Yitzchak to rule on her question?
1. The ME'IRI and TOSFOS in Avodah Zarah (7a, DH ha'Nish'al) explain that Rav Yitzchak was permitted to overrule the stringent ruling of Rabah bar bar Chanah since there were grounds to assume that he had made a mistake (his eyes were sore and he could not see the Mar'eh properly). This implies that under normal circumstances a second Chacham may not rule leniently when another Chacham previously ruled stringently. Only when there is a strong reason to assume that the first Chacham made a mistake may the second Chacham rule leniently.
3. TOSFOS (DH a'Gemarei, and in Chulin 44b, DH Heichi) explains that the second Chacham may overrule the first Chacham based on a Mesorah, a tradition that he has received. However, he may not overrule the first Chacham's ruling based only on his own logical reasoning.
HALACHAH: The REMA (YD 242:31) writes that when one Chacham rules stringently, a second Chacham may not overrule the first Chacham's decision based on his own logic (unless he finds that the first Chacham made a mistake and was "To'eh b'Devar Mishneh"). However, he may overrule the first Chacham's decision based on a Mesorah, as Tosfos states. The SHACH (YD 242:55) rules that a second Chacham should not overrule the stringent ruling of the first Chacham even based on a Mesorah.
The MISHKENOS YAKOV (#59) rules in accordance with the REMA. He explains that the REMA means that when the second Chacham's Mesorah, from a Gadol ha'Dor, would cause the first Chacham to change his mind, then he may overrule the decision of the first Chacham. If the first Chacham, though, would not accept the ruling of the Chacham from whom the Mesorah came, then the second Chacham may not overrule the first Chacham's decision based on his Mesorah.

OTHER D.A.F. RESOURCES
ON THIS DAF