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Shabbos 131

131b

QUESTION: The Gemara says that Rebbi Eliezer needs a separate verse to teach that the *preparations* for each of various Mitzvos are permitted to be done on Shabbos, even though they involve doing Melachah. The Gemara explains why *one* verse does not suffice to serve as the source for doing the preparations for all Mitzvos on Shabbos.

However, normally, when there are two verses that teach that a certain Halachah applies to two different items, we can learn that it applies to all other items through the use of a "Mah ha'Tzad." Why, then, does the Gemara not suggest that we can learn Rebbi Eliezer's Halachah that the preparations of a Mitzvah override Shabbos from *two* verses, through a "Mah ha'Tzad?"

ANSWERS:

(a) TOSFOS (DH Iy m'Omer), citing Rav Poras, answers that the Gemara must have known that there was some question (Pircha) that prevented the Halachah from being derived through a "Mah ha'Tzad." That is, had the Gemara suggested a Mah ha'Tzad, it would have countered that each of the cases mentioned has something which makes it unique from all the other cases, such that it cannot be learned from a Mah ha'Tzad.

(b) Tosfos suggests a second answer: Indeed the Gemara could have derived this Halachah from a "Mah ha'Tzad." Nevertheless, there it is feasible that a verse was written in the Torah to teach explicitly a Halachah that otherwise could have been deduced through a "Mah ha'Tzad," in order to make it more clear. (This is known as "Tarach v'Kasav La Kra"; the Gemara actually only applies this principle to what is learned from a Kal v'Chomer, see Pesachim 18b etc.) Therefore, the Gemara does not feel it necessary to show that the Halachos in question could not have been learned from a Mah ha'Tzad.

However, if the Halachah could have been derived from *one* verse through a "Binyan Av," there would have been no need for the verse to mention it explicitly. A "Binyan Av" is just as clear as an explicit teaching.

QUESTION: The Gemara says that according to Rebbi Eliezer, the Halachah that preparations for the Mitzvah of Lulav override Shabbos is derived from the word "ba'Yom" which appears in a verse discussing Lulav. The Rabanan, though, maintain that that phrase is needed to teach that the Mitzvah of Lulav is performed only during the day and not at night, because we might have compared Lulav to Sukah through a Gezeirah Shavah between the two (from the words "Shiv'as Yamim") and assumed that just like the Mitzvah of Sukah applies at night, so, too, does the Mitzvah of Lulav.

Rebbi Eliezer, though, does not need a second phrase to teach that the Mitzvah of Lulav is not performed at night. It seems that Rebbi Eliezer maintained that there was no reason to compare Sukah to Lulav; he argued that there is no Gezeirah Shavah of "Shiv'as Yamim." However, in the following lines of the Gemara, Rebbi Eliezer says that the reason why the preparations for the Mitzvah of Sukah override Shabbos is because of the Gezeirah Shavah comparing Sukah to Lulav!

If Rebbi Eliezer accepts the Gezeirah Shavah between Lulav and Sukah, then why does he not require another verse to teach that the Mitzvah of Lulav is performed only during the day (and not at night as well, like Sukah)?

ANSWERS:

(a) TOSFOS (DH Shiv'as) answers that although Rebbi Eliezer agrees that there is a Gezeirah Shavah, he maintains that it cannot be applied when the very words used for the Gezeirah Shavah -- "Shiv'as Yamim" ("seven days") -- seem to preclude the law derived from it! That is, the word "days" cannot teach that just like the Mitzvah of Sukah is performed at night, so, too, the Mitzvah of Lulav is performed at *night*, because such a teaching would contradict the simple meaning of the words used for the Gezeirah Shavah -- "seven *days*."

(b) The RE'AH and RITVA answer that Rebbi Eliezer maintained that the Sukah and Lulav cannot be compared as far as night is concerned for another reason. With regard to Sukah, the Halachah is that the Mitzvah applies *all* day and *all* night. This Halachah cannot be applied to Lulav, because the Torah certainly does not require that the Lulav be held all day and all night. On the other hand, it is unacceptable to suggest that the Gezeirah Shavah teaches that one must pick up the Lulav *once* at night, because then the Halachah with regard to Lulav is not similar to the Halachah with regard to Sukah, from which the Halachah is derived.

(c) The RASHBA explains that Rebbi Eliezer indeed learns from a verse that the Mitzvah of Lulav does not apply at night: from the verse "Shiv'as *Yamim*" (which incidentally is the verse used for the Gezeirah Shavah). However, the Rabanan maintain that *two* verses (Shiv'As Yamim, ba'Yom) are necessary to teach the the Lulav is not taken at night, since there are two different Halachos with regard to the Mitzvah of Lulav that are only done by day.

The first Halachah is that in the *Beis ha'Mikdash*, the Mitzvah is to hold the Lulav for seven days. The second Halachah is that *outside* of the Beis ha'Mikdash, the Lulav is held only the first day. Consequently, one verse is needed to teach that the Lulav is not held at night in the Beis ha'Mikdash, and another verse is needed to teach that it is not held at night outside of the Beis ha'Mikdash. Rebbi Eliezer, though, maintains that the Halachah that the Lulav is not held at night outside of the Beis ha'Mikdash is derived from the Halachah with regard to inside the Beis ha'Mikdash, and thus only one verse is needed to teach that it is not held at night.