1) PREPARING FOR SHABBOS AND "BITUL TORAH"
QUESTION: The Gemara relates how Rebbi Avahu, Rav Huna, Rabah, Rav Yosef, and many other Amora'im would physically involve themselves in the preparations for Shabbos. The Gemara in Kidushin (41a) adds that they performed the preparations for Shabbos even though they had servants that could do it for them.
The Gemara in Moed Katan (9a) states that learning Torah is more important than all of the other Mitzvos, so that if one is presented with the opportunity to do the Mitzvah of learning Torah and the opportunity to do another Mitzvah, the Mitzvah of learning Torah takes precedence (if someone else can do the other Mitzvah). (If no other person can do the other Mitzvah, then one may interrupt his Torah learning in order to perform it, since the purpose of learning Torah is to perform the Mitzvos.) Since there were others who could do these preparations for Shabbos, why were these Amora'im permitted to stop learning Torah? (MISHNAH BERURAH in SHA'AR HA'TZIYUN OC 250:9)
ANSWERS:
(a) The SHA'AR HA'TZIYUN writes that when the Gemara in Moed Katan says that one does not stop learning Torah in order to perform a Mitzvah that can be done by someone else, it refers to a Mitzvah that requires that a certain objective be accomplished. Since that objective can be accomplished by someone else, one may not stop learning Torah to do it himself. When the Gemara there mentions a Mitzvah that cannot be done by someone else, it refers to a Mitzvah that obligates the person himself to be involved, such a wearing Tefilin. Preparing for Shabbos falls into the latter category; the person himself is required to be involved in the preparations for Shabbos, and not merely to ensure that the preparations are accomplished. (This answer is problematic, because if the Mitzvah of preparing for Shabbos obligates the person himself to be involved, how can the Gemara in Kidushin prove from these Amora'im that it is better for a person to perform a Mitzvah himself than to appoint a Shali'ach to do it? A Shali'ach cannot perform a Mitzvah that another person is personally obligated to perform!)
(b) The Mitzvah of honoring the Shabbos is a very important Mitzvah, and thus it requires that one even stop learning Torah in order to fulfill it. (Ibid.)
(c) Perhaps these Amora'im did not stop learning Torah at all. Rather, they continue to learn Torah at the same time that they performed their Shabbos preparations.

119b----------------------------------------119b

2) PEOPLE OF TRUSTWORTHINESS
QUESTION: Rava taught that the Beis ha'Mikdash was destroyed because there ceased to exist men of trustworthiness. The Gemara challenges this from a teaching of Rav Katina, who said that even during the time of the collapse of Yerushalayim, when the Beis ha'Mikdash was destroyed, "men of trustworthiness did not cease [to exist]." The Gemara concludes that when it came to business, there were no trustworthy people. In Torah, though, there were still trustworthy people whom one could trust when they said that they did not know Torah.
What is so noteworthy about the fact that people were proud to be honest and say that they did not know Torah?
ANSWER: HA'GAON RAV SHLOMO FISHER shlit'a (author of Sefer Beis Yishai) explained the words of the Gemara here as follows (as heard from him in person):
The Sefer ha'Akeidah and Abarbanel explain that Hash-m gave the Jewish people a special blessing that "men of trustworthiness in Torah would not cease to exist." The essence of this blessing is as follows: We find in the Torah (Devarim 31:21) that Hash-m has promised that the Torah will never be forgotten. In order for the Torah not to be forgotten, Hash-m ensured that when the elders do not know the Torah, they will admit it. This prevents the forging and misconstruing of the Torah.
Rav Fisher added that this may also explain the choice of the psalm-of-the-Day recited on Shemini Atzeres, chapter 12 of Tehilim. This psalm does not seem to be related in any way to Torah (Simchas Torah) or to Shemini Atzeres. "Save us Hash-m, because... no one can be trusted anymore, everyone speaks falsely... the words of Hash-m are pure words, like finely refined silver. You, Hash-m, will protect them and save them forever...."
RAV SAMSON RAPHAEL HIRSCH explains that there is a fine correlation between Pesach and Shavuos, and between Sukos and Shemini Atzeres. The first pair, Pesach and Shavuos, represents the "birth" of the nation with the Torah. The second pair, Sukos and Shemini Atzeres, represents the continuity of the nation with the Torah.
Accordingly, chapter 12 of Tehilim is most appropriate for Shemini Atzeres, because the subject of that psalm is the special blessing that men of trustworthiness in Torah will never cease, which, as we explained, is a safeguard for the continuity of the Torah. Since Shemini Atzeres is the time that represents the perseverance of the nation and the protection of the Torah, it is most appropriate to discuss on this day the blessing that Hash-m gave us, that the Torah will be preserved throughout all of the generations: "No one can be trusted anymore, everyone speaks falsely... [but] the words of Hash-m (the Torah) are pure... You, Hash-m, will protect them, You will preserve them from this generation forever."

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