1) UNDERSTANDING THE OPINION OF REBBI YEHUDAH
QUESTION: The Gemara relates that when the Talmidim of Rav ate a meal one Friday afternoon, they asked Rav Hamnuna Saba to check whether nightfall had arrived. If it had, they would recite Birkas ha'Mazon, remove the tables (Akiras ha'Shulchan), and recite Kidush in order to start the Shabbos meal. Rav Hamnuna Saba replied that there was no need to check if nightfall had come, because the very onset of Shabbos itself makes the meal designated for Shabbos.
The RASHBAM explains that since one is not permitted to eat before Kidush, he is not required to recite Birkas ha'Mazon or remove the table in order to show that his meal is for the sake of Shabbos. Rather, it suffices to be "Pores Mapah" (spread a cloth over the meal) and recite Kidush.
The Gemara here is difficult to understand for two reasons.
First, Rav Hamnuna Saba apparently ruled like Shmuel (100a), who says that when Shabbos arrives while one is in the middle of a meal, he needs merely to be "Pores Mapah" and recite Kidush. However, the RASHBAM (100a) explains that Shmuel follows Rebbi Yosi who says that according to the letter of the law one is permitted to continue his meal when Shabbos arrives and does not have to stop and recite Kidush. According to Rebbi Yosi, the onset of Shabbos does not prohibit one from continuing his meal. Only as an added stringency does Shmuel require that one be "Pores Mapah" and recite Kidush. Why, then, does Rav Hamnuna say that the onset of Shabbos itself designates the meal for Shabbos, because the onset of Shabbos prohibits one from continuing to eat? (DEVAR SHMUEL)
Second, the Talmidim of Rav were ready to recite Birkas ha'Mazon and remove the table if Shabbos had arrived. They apparently ruled like Rebbi Yehudah, who says that when Shabbos arrives during one's meal, he must recite Birkas ha'Mazon and remove the table (in contrast to Shmuel's opinion). On the other hand, Rav Hamnuna Saba ruled that one merely needs to be "Pores Mapah" and recite Kidush, in accordance with the opinion of Rebbi Yosi.
If Rav Hamnuna Saba ruled like Rebbi Yosi, why did he present an argument to the Talmidim of Rav based on logic? He should have told them simply that the Halachah follows the opinion of Rebbi Yosi and not the opinion of Rebbi Yehudah.
ANSWER: The RASHBAM earlier (100a) explains that Rebbi Yehudah requires "Akiras ha'Shulchan" (removal of the table) and not just "Pores Mapah." The Rashbam infers this from the words of Shmuel who says, "The Halachah is not like Rebbi Yehudah... rather, one must be 'Pores Mapah' and recite Kidush," which imply that Shmuel understood that Rebbi Yehudah requires "Akiras ha'Shulchan."
The Talmidim of Rav interpreted Rebbi Yehudah's opinion in the same manner, and, since they ruled like Rebbi Yehudah, they required "Akiras ha'Shulchan." Rav Hamnuna Saba argued that Rebbi Yehudah requires only "Pores Mapah," because "Shabbos designates itself" through the prohibition against eating before Kidush. (That is, according to Rav Hamnuna Saba it is necessary to be "Pores Mapah" according to Rebbi Yehudah, but not for the same reason that Shmuel says. Rav Hamnuna requires it "me'Ikar ha'Din," while Shmuel requires it only as an added stringency.)
This explanation answers the first question. When Rav Hamnuna Saba said that the onset of Shabbos itself designates the meal for Shabbos and therefore only "Pores Mapah" is required, it was his own view that he expressed, and not Shmuel's view of Rebbi Yehudah's opinion. According to Rav Hamnuna, Rebbi Yehudah is of the opinion that one may not eat before Kidush, and that "Pores Mapah" suffices for Kidush.
This also answers the second question. Rav Hamnuna Saba did not argue with the Talmidim of Rav because he ruled that the Halachah follows Rebbi Yosi. They both agreed that the Halachah follows Rebbi Yehudah. Their argument revolved around how to interpret Rebbi Yehudah's opinion. (M. KORNFELD)

105b----------------------------------------105b

2) "I AM NOT A CHACHAM, I AM NOT A CHOZEH, I AM NOT A YACHID" -- THE CRYPTIC INTRODUCTION OF RAV NACHMAN
QUESTION: Rav Nachman bar Yitzchak asserted that even though one is allowed to recite Kidush ha'Yom ("Vayechulu...") throughout the day of Shabbos if he neglected to recite it at night, he preferably should say it at night because "Chavivah Mitzvah b'Sha'ato," a Mitzvah is most cherished when it is done at its proper time.
He was asked what the difference is between Kidush and Havdalah. Havdalah is supposed to be delayed and not recited immediately at the conclusion of Shabbos, even though that is its proper time. Rav Nachman bar Yitzchak answered, "I am not a Chacham, I am not a Chozeh, I am not a Yachid. I am a Gamar and a Sadar, and they say in the Beis Midrash the same thing that I say, that there is a difference between the onset of the day (Kidush) and the conclusion of the day (Havdalah). When it comes to Kidush, the sooner we recite it, the better, for we show how beloved it is to us. When it comes to Havdalah, the more we delay it, the better, in order not to make it appear like a burden upon us."
What is the meaning of this unusual introduction, "I am not a Chacham, I am not a Chozeh, I am not a Yachid... and they say in the Beis Midrash the same thing that I say," with which Rav Nachman prefaced his answer?
ANSWER: The OR SAME'ACH (Hilchos Shabbos 29:12) offers a brilliant interpretation of Rav Nachman's words. Rav Nachman's answer is based on the fact that Havdalah should be delayed, in contrast to Kidush which should be recited promptly. When to recite Havdalah is actually the subject of a dispute between Amora'im earlier (102b-103a). The Gemara there discusses the order of the blessings when Yom Tov occurs on Motza'ei Shabbos, when one must recite both Kidush (for Yom Tov) and Havdalah (for Shabbos). Seven different Amora'im and Tana'im argued whether the blessing of Havdalah is said first or the blessing of Kidush is said first (see Chart there).
The Amora'im who said that Kidush must be recited first were Rav, Levi (according to our text of the Gemara, in contrast to the Rashbam's text), the Rabanan, and Mar brei d'Ravna. These Amora'im agreed with Rav Nachman bar Yitzchak's conclusion that Havdalah should be delayed.
The Amora'im who said that Havdalah must be recited first, in contrast to Rav Nachman's opinion, were Shmuel and Rabah, as well as the Tana, Rebbi Yehoshua ben Chananya. (Rebbi Yehoshua is mentioned twice. He is quoted first by Marta and then by Rebbi.)
When Rav Nachman presented his case that one should delay Havdalah, he chose to allude to those who preceded him on the topic. He referred to six of the seven, and indicated that three agreed with him and three argued with him.
When he said, "I am not a Chacham," he implied that he does not agree with the one who was called a Chacham. Rebbi Yehoshua ben Chananya is called "Chakima d'Yehuda'i," the Chacham of the Jews (Bechoros 9b).
He said, "I am not a Chozeh," a reference to Shmuel, who was an expert astronomer and observed ("Chozeh") the stars and celestial bodies (Berachos 58b; Tosfos to Ta'anis 7a).
He said, "I am not a Yachid," a reference to Rabah (bar Nachmani), who attested, "I am a Yachid (peerless) in the study of Nega'im, and I am Yachid in the study of Ohalos" (Bava Metzia 86a).
After he alluded to those with whom he argued, he then hinted to those with whom he agreed.
"I am Gamar (learned)" refers to Levi. The Gemara (Sanhedrin 17b) says that whenever mention is made of "the one who learned (Gamar) before the Chachamim," it means Levi.
"I am Sadar (I organize my learning)" refers to Rav, who is called "Reish Sidra d'Bavel" (Chulin 137b).
Finally, Rav Nachman said that "they say in the Beis Midrash the same thing that I say," an allusion to the anonymous Rabanan of the Beis Midrash who also said that Havdalah should be delayed.
(The only one to whom Rav Nachman did not refer was Mar brei d'Ravna. Since they were contemporaries, Rav Nachman felt no need to address his opinion.)
A similar approach is suggested by RAV REUVEN MARGOLIYOS (in CHEKER SHEMOS V'KINUYIM #4; see footnote 8 there).

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