1) TRAVELING TO LEARN TORAH
QUESTION: The Mishnah teaches that a person who is en route to perform a Mitzvah is exempt from the Mitzvah of Sukah. RASHI gives three examples: one who is traveling to greet his Rebbi, one who is traveling to learn Torah, and who is traveling to redeem captives.
Why is one who is traveling to learn Torah exempt from the Mitzvah of Sukah? The Gemara in Moed Katan (9a) teaches that a person must interrupt his Torah study in order to perform any Mitzvah which cannot be performed by others. Why, then, does the act of traveling to learn Torah exempt a person from the Mitzvah of Sukah? Traveling to learn Torah certainly is not a greater Mitzvah than the learning of Torah itself.
Moreover, the Yerushalmi (Berachos 1:2) says that even Rebbi Shimon bar Yochai would stop learning in order to perform Mitzvos such as Sukah and Lulav, since "if one learns Torah but does not accept upon himself to perform the Mitzvos, it would have been better had he not been created." The same should apply to one who is traveling to learn Torah; he should be required to interrupt his traveling in order to perform the Mitzvah of Sukah.
(The MAHARACH OR ZARU'A #183 says even more than Rashi: even when one has arrived at his place of learning and has started to learn, he is exempt from Mitzvos for the entire time that he learns.)
ANSWERS:
(a) The OR SAME'ACH (Hilchos Talmud Torah 3, and in MESHECH CHOCHMAH, Parshas Ki Savo 28) quotes the RI of KURVEILLE (as cited by Tosfos to Kesuvos 17a, DH Mevatlin), who says that even though the Mitzvah of learning Torah does not exempt one from performing the Mitzvah of Hotza'as ha'Mes (burial of the dead), the Mitzvah of "Shimush Talmidei Chachamim" does override the Mitzvah to bury the dead (even in the case of a "Mes Mitzvah"). "Shimush Talmidei Chachamim" refers to learning the reasons and explanations of the Torah directly from a Rebbi. It is not in the same category as normal Torah study, because it is done only through close interaction with a Rebbi who transmits the tradition that he has received for the reasons and explanations of the Mitzvos. Therefore, it overrides even a Mitzvah which cannot be done by someone else.
The Mishnah here refers to this type of learning. When the Talmidim travel to the home of their Rebbi in order to learn Torah from him, they have the status of those who are fulfilling "Shimush Talmidei Chachamim," which overrides other Mitzvos.
(b) The CHAZON YECHEZKEL quotes the VILNA GA'ON (in the beginning of Pe'ah) who points out that every word of Torah that a person learns is another Mitzvah. This might explain why one must stop learning Torah in order to fulfill another Mitzvah, but one who is on the way to learn Torah does not have to stop traveling in order to perform a Mitzvah. When one is involved in the Mitzvah of learning Torah, he fulfills a Mitzvah with every word that he learns. If the opportunity to perform another Mitzvah arises, he must do that Mitzvah first before he begins to fulfill another Mitzvah of Talmud Torah (by learning the next word). His fulfillment of the second Mitzvah is not an interruption of the Mitzvah of Talmud Torah, because he completed one Mitzvah of Talmud Torah and did not yet start the next, when the other Mitzvah needed to be performed. In contrast, when one travels to learn Torah, the act of traveling itself is one Mitzvah, and therefore he is not required to interrupt it in order to perform another Mitzvah.
2) HALACHAH: ONE WHO IS INVOLVED IN A MITZVAH IS EXEMPT FROM OTHER MITZVOS
QUESTION: The Gemara teaches that one who is involved in a Mitzvah is exempt from the Mitzvah of Keri'as Shema. This is the source for the general rule, "ha'Osek b'Mitzvah Patur Min ha'Mitzvah" -- "One who is involved in one Mitzvah is exempt from another Mitzvah."
If one is exempt from a Mitzvah while he is involved in the performance of another Mitzvah, then every man who wears Tzitzis or Tefilin should be exempt from all other Mitzvos! This certainly is not the Halachah, though. When exactly does involvement in one Mitzvah exempt a person from another Mitzvah? (TOSFOS DH Sheluchei Mitzvah)
ANSWERS:
(a) TOSFOS answers that only when the second Mitzvah will interrupt one's performance of the first Mitzvah is one exempt from the second Mitzvah. If the fulfillment of the second Mitzvah will not interfere with one's performance of the first Mitzvah (such as in the case of the Mitzvah of Tzitzis or Tefilin), he is not exempt from the second Mitzvah.
The OR ZARU'A questions the answer of Tosfos. It is obvious that one may not interrupt one Mitzvah in order to perform another. Why would one have thought that one Mitzvah takes precedence over another, had the verse not taught otherwise?
Perhaps Tosfos learns from the verse that one who is involved in one Mitzvah is exempt from other Mitzvos even in a case where the opportunity for the second Mitzvah will pass if it is not done right away. One might have thought that in such a situation, he should interrupt the performance of the first Mitzvah and fulfill the second Mitzvah. The verse teaches that even in such a case, one may not interrupt the first Mitzvah to perform the second. (M. KORNFELD)
(b) The RASHBA in the name of RAV HAI GA'ON, the MAGID MISHNEH (Hilchos Sukah 6:4) in the name of the GE'ONIM, and the OR ZARU'A (Hilchos Sukah) explain that as long as a person is involved in the preparations for a Mitzvah, such as one who is traveling in order to perform a Mitzvah, he is not obligated by the Torah to perform other Mitzvos even if they do not distract him from the first Mitzvah. Hash-m does not expect a person to do two things at once.
Accordingly, with regard to Tzitzis and Tefilin, one has already done all that was necessary in order to prepare for the Mitzvah. The man who wears Tzitzis or Tefilin is now in the process of passively fulfilling the Mitzvah and not in the process of preparing to fulfill the Mitzvah. The exemption from other Mitzvos applies only when one has not yet fulfilled the first Mitzvah and is involved in the preparatory stages of fulfilling the Mitzvah.
(c) The RAN suggests a compromise. He agrees with the Rashba that one is exempt from the second Mitzvah even if its performance does not distract him from the first Mitzvah. However, if there is a way for him to fulfill the second Mitzvah and still perform the first Mitzvah in its normal manner, then he is not exempt from the second Mitzvah (as the Ran writes, "why not fulfill a Mitzvah if nothing is lost while doing so?"). Only when he must change the normal way in which he performs the first Mitzvah in order to fulfill the second Mitzvah is he exempt from the second Mitzvah.
(According to the Ran, it is possible that the obligation to do the second Mitzvah does not stem from the normal obligation to perform Mitzvos, but rather from the requirement that one avoid disgracing a Mitzvah. Technically, he may be exempt since he is involved in another Mitzvah, but in practice -- since he could perform the second Mitzvah without any deviation from his normal way of performing the first Mitzvah -- he must perform the second Mitzvah in order not to disgrace it. -M. KORNFELD)
HALACHAH: The REMA (OC 38:8) cites the opinion of the Ran as the Halachah. When there is a way to fulfill the second Mitzvah and still perform the first Mitzvah in its normal manner, he is not exempt from the second Mitzvah. If there is no way to fulfill the second Mitzvah and perform the first Mitzvah in its normal way, he is exempt from the second Mitzvah. (See also Insights to Berachos 11:1 and Bava Metzia 82:2.)

25b----------------------------------------25b

3) WHY A MOURNER IS NOT EXEMPT FROM THE MITZVAH OF SUKAH
QUESTION: Rebbi Aba bar Zavda says in the name of Rav that an Avel (mourner) is obligated to fulfill the Mitzvah of Sukah. The Gemara says that without his statement, one might have thought that an Avel is exempt since he is distressed ("Mitzta'er"), and one who is distressed is exempt from the Mitzvah of Sukah. Rebbi Aba bar Zavda teaches that distress exempts a person from the Mitzvah of Sukah only when the distress comes from an external source. In the case of an Avel, the mourner causes his own anguish, and therefore he is not included in the category of "Mitzta'er." He is obligated to perform the Mitzvah of Sukah because "he should settle his mind."
The Gemara implies that if the Avel does not "settle his mind," he will not be able to fulfill the Mitzvah of Sukah and he is exempt. This is difficult to understand. The distress of an Avel is not related to his sitting in the Sukah in any way. Why should it prevent him from fulfilling the Mitzvah? The only reason why one who is "Mitzta'er" is exempt from the Mitzvah of Sukah is because of the principle of "Teshvu k'Ein Taduru" -- one must live in the Sukah during Sukos in the same manner in which he lives in his house during the rest of the year. Normally, when one becomes uncomfortable in his house, he leaves it (TOSFOS 26a, DH Holchei). If, however, a person is "Mitzta'er" in such a way that leaving the house or the Sukah will not relieve his distress, then he certainly is not exempt from the Mitzvah of Sukah (as the MORDECHAI (#740) writes in the name of the YERE'IM, and as is clear from many Rishonim; see Rashi 26a, DH Mitzta'er). Why, then, does the Gemara say that an Avel must "settle his mind" and alleviate his distress? His distress is not the type that exempts him from the Mitzvah of Sukah! (MAHARIK, Shoresh 176, cited in an addition to the MORDECHAI here.)
ANSWERS:
(a) The ROSH apparently is bothered by this question. He explains that an Avel prefers to be alone and to sit in the dark. If he leaves the Sukah, he will be more "comfortable" (according to his subjective experience of "comfort"), because he will no longer be with other people (who stay in the Sukah) or be in a place with food to eat. For the Avel to remain in the Sukah will cause him more distress; he wishes that he could avoid the relaxing environment of the Sukah. (In other words, the Avel experiences distress in the Sukah because of the lack of distress there. The distress he experiences in the Sukah is that as long as he is in the joyful atmosphere of the Sukah he is unable to experience the distress that he seeks for himself.)
If, however, being in the Sukah causes the Avel more distress, then why indeed is he not exempt? The Gemara teaches that even though he experiences discomfort by being in the Sukah, he is not exempt from the Mitzvah because his discomfort is a result of his own choice to feel uncomfortable in the Sukah.
(b) RASHI (28b, DH Bar mi'Metalalta) implies that a person in distress, such as an Avel, usually feels more comfortable in the open outdoors than in an enclosed Sukah. Why, then, is an Avel not exempt from the Mitzvah of Sukah due to his distress?
The RITVA answers this question with a novel interpretation of the Gemara's words. When an Avel enters the Sukah, the joyful atmosphere there contributes to the alleviation of his distress and he begins to feel better. Since the cause of his distress is psychological and not physical, once he overcomes his initial apprehension and enters the Sukah the atmosphere of the Sukah relaxes him and makes him less distressed, so that he feels completely comfortable in the Sukah.
(The TAZ (OC 640:7-8) suggests that perhaps any type of distress exempts a person from the Mitzvah of Sukah, even if the distress is unrelated to the Sukah, because the Mitzvah requires concentration and one who is distressed is unable to concentrate properly. When one sits in a Sukah, in order to fulfill the Mitzvah he must have in mind that Hash-m protected the Jewish people in Sukos when they left Mitzrayim (Vayikra 23:43). A person who is distressed is unable to have such concentration, and therefore he is exempt.)
4) "YICHUD" IN A SUKAH
QUESTION: The Gemara says that a Chasan and the members of his wedding party are exempt from the Mitzvah of Sukah during the seven days of the wedding celebration, because they are obligated to perform the Mitzvah of rejoicing in the Chupah and not in the Sukah. The Gemara asks that they should simply make the Chupah inside of the Sukah.
Abaye answers that the Chupah is not made in the Sukah because of the problem of Yichud. There is a concern that the Chasan might leave the Sukah to fulfill his needs, and his Kalah will be left alone with one of the members of the wedding party.
Rava says that the Chupah is not made in the Sukah because of the distress of the Chasan. According to RASHI, this means that the Chasan will be embarrassed to express his happiness with his Kalah when others are able to see him through the open wall of the Sukah. According to the ME'IRI, this means that the Sukah is too narrow for him to be able to invite all of his friends.
Why does Abaye say that there is a problem of Yichud? The Halachah is that when a woman's husband is in the city, the prohibition of Yichud does not apply, because he might walk in at any time (Kidushin 81a). In this case, the Chasan certainly is in the city, as he walked out of the Sukah merely to fulfill his needs. Why should Yichud pose a problem?
Moreover, according to Rashi's explanation, when Rava says that the Chasan is exempt because of his distress, he means that the Chasan is distressed that he cannot express his happiness with his Kalah because others can see him through the open side of the Sukah (an ordinary Sukah, in the times of the Gemara, had only three walls). If the Sukah has only three walls and people are able to see inside of it, why does Abaye say that there is a problem of Yichud? There is no prohibition of Yichud when the place is visible to others.
ANSWERS:
(a) The MAHARSHAM (in "Mafteichos" to Teshuvos, Even ha'Ezer 2:76) writes that when Abaye says that the Chasan is exempt from the Mitzvah of Sukah because of the concern for Yichud, he does not mean the prohibition of Yichud. There certainly is no prohibition of Yichud when the Chasan goes out of the Sukah and his friend is left with his Kalah, because the Chasan is still in the city and people can see into the Sukah through the open side. Rather, Abaye means that there might be a suspicion of Yichud. The Chasan -- if he goes out and leaves his Kalah alone in the Sukah -- might have misgivings about his Kalah and suspect her of being with another man. In order to prevent the Chasan from having such suspicions, he is exempt altogether from the Mitzvah of Sukah. (See also the comments of Rav Elyashiv shlit'a in HE'OROS B'MASECHES SUKAH.)
(b) Alternatively, perhaps Abaye means that there is a prohibition of Yichud, even though the husband is in the city. The Gemara in Kidushin (ibid.) says that even when the husband is in the city, a man who is very friendly with the wife is prohibited to be alone with her. In this case, some of the members of the wedding party (Shoshvinim) are very friendly with the Kalah, and thus there is a concern for Yichud even when the Chasan is in the city. (HE'OROS B'MASECHES SUKAH in the name of Rav Elyashiv shlit'a)
(Perhaps this approach also answers the second question. When the Kalah is left alone with a Shoshvin, the problem of Yichud remains even in an area that is only partially secluded.)

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