1) LEARNING THE LAWS OF "TUM'AS OHALIM" FROM THE "MISHKAN"
QUESTION: The Gemara derives from the laws of the Mishkan that Pishtan can become Tamei if it serves as an Ohel over a dead body. The Torah states, "And he spread the covering (Ohel) over the Mishkan" (Shemos 40:19). A Gezeirah Shavah with the verse discussing Tum'as Ohalim, "When a person dies in an Ohel..." (Bamidbar 19:14), teaches that Pishtan that serves as an Ohel can become Tamei with Tum'as Ohel.
RASHI (DH Mah Tachton) explains that the word "Mishkan" refers to the ten lengths of Pishtan (and woven material) that were hooked together to form one large piece and spread over the Mishkan, and which served as its lower covering. The word "Ohel," when describing a covering of the Mishkan, refers to the eleven lengths of goat-hair material which were connected into one large piece that was placed above the lower covering of Pishtan.
According to Rashi's explanation, how can we learn from the verse, "And he spread the covering (Ohel) over the Mishkan," that the covering of Pishtan becomes Tamei? The "Ohel" that that verse mentions is the covering of goat-hair!
ANSWERS:
(a) TOSFOS (DH va'Yifros) and the RAMBAN explain that even though the word "Ohel" usually refers to the covering of goat-hair over the Mishkan, in this verse it must be referring to the lower covering of Pishtan, because the verse states that this Ohel was spread directly upon the Mishkan. Since the covering of Pishtan was the lowest covering, it obviously was placed on the Mishkan first.
(b) Tosfos suggests further that the verse, "Mishkan Ohel Mo'ed," teaches that the word "Mishkan" (which, as mentioned above, refers specifically to the covering of Pishtan) is synonymous with "Ohel." Accordingly, not only is it inaccurate to cite the verse, "And he spread the covering (Ohel) over the Mishkan," in order to prove that the Pishtan covering is considered an Ohel (since that verse is referring to the goat-hair covering), but it is unnecessary. It is obvious that the Pishtan covering is an Ohel, since it is called "Mishkan." (Rashi, DH Mishkan Karuy, also alludes to this approach.)
Why, then, does the Gemara cite the verse, "And he spread the covering (Ohel) over the Mishkan" (Shemos 40:19), as the source for the Halachah that Pishtan is called an Ohel? The Gemara cites this verse because the end of the verse refers to the covering of Pishtan as "Mishkan," and we find elsewhere that "Mishkan" and "Ohel" are analogous. The word "Ohel" in that verse (Shemos 40:19), however, is not at all pertinent to the subject of the Gemara here (RITVA). Alternatively, the Gemara indeed is not citing the accurate source for the Halachah, but rather it is relying on another verse (the one that equates "Mishkan" with "Ohel").
2) THE "TACHASH" ANIMAL
QUESTION: Rebbi Nechemyah compares the Tachash animal with the "Tala Ilan" animal, which has very colorful fur. Rav Yosef, upon hearing this, exclaimed, "That is why the Aramaic word for Tachash is 'Sasgona' -- it rejoices (Sas) in its many colors (Gavna)."
Why was Rav Yosef looking for a meaning for the Aramaic translation of "Tachash"? Perhaps "Sasgona" is simply the Aramaic name for the animal. Why does it have to have any deeper meaning, such that Rav Yosef needed an acronym to explain it?
ANSWER: RAV HESCHEL of Krakow (CHANUKAS HA'TORAH, Parshas Terumah) explains that since the Tachash appeared only for Moshe Rabeinu (as the Gemara says on 28b), it was never known to any other person who would be able to give it a name in his own language, like Aramaic. Therefore, Rav Yosef was bothered how the Tachash ever acquired an Aramaic name. The Targum should have translated Tachash as "Tachash," and not as "Sasgona"! It must be that the name "Sasgona" is merely descriptive, and that is why Rav Yosef was happy to find out how it describes the Tachash.

28b----------------------------------------28b

3) HALACHAH: TOUCHING AND BENEFITING FROM "MUKTZAH"
QUESTION: In the Mishnah, Rebbi Eliezer and Rebbi Akiva argue whether one may light Shabbos candles with a small piece of cloth that was folded into a wick. In the first explanation of their argument, the Gemara says that they are arguing in a case in which Yom Tov falls on Friday. One must hold the flame to the wick until most of it is lit (that is, until the flame takes hold nicely). Rebbi Eliezer forbids using such a wick, because before the flame takes hold to most of it, it will lose its status of a garment and will become a useless fragment of a garment and thus it is Muktzah (because of "Nolad").
(a) May we infer from the Gemara here that one is prohibited from even touching Muktzah on Shabbos and Yom Tov?
(b) Even if one does not have to wait until most of the wick catches fire, when the wick diminishes to less than three by three Etzba'os on Shabbos, it loses its status of a garment and becomes Muktzah. Why, then, is one permitted to eat by its light and derive benefit from the flame on Shabbos, if the flame is Muktzah? The Gemara later (43a) teaches that an egg that is Muktzah may not be used to support a bench!
ANSWERS:
(a) The Yerushalmi (in Beitzah) says that one may cover an egg laid on Yom Tov with a utensil as long as he does not touch it with the utensil. This implies that it is forbidden to touch Muktzah on Shabbos or Yom Tov even with another object.
The MAGID MISHNEH (Hilchos Shabbos 25:23) explains that the prohibition against touching Muktzah applies only to an egg, because it moves when it is touched due to its shape. This is the Halachah (SHULCHAN ARUCH OC 310:6 and 322:1; MISHNAH BERURAH 310:22 and 322:3). Therefore, one is permitted to touch any other Muktzah object.
Why, then, in the case of the Gemara here, may one not continue lighting the wick even though it is Muktzah? Perhaps it is prohibited because a wick is so insubstantial that it inevitably will be moved when one touches a flame to the wick (this is similar to the Magid Mishneh's understanding of the Yerushalmi). (The RASHBA, however, suggests another reason, as described below.)
(b) With regard to deriving pleasure on Shabbos or Yom Tov from an item that is Muktzah, TOSFOS in Pesachim (26b, DH Chadash) implies that deriving pleasure from Muktzah is not prohibited. Why, then, does the Beraisa prohibit resting a bench on an egg?
A closer look at the Beraisa (on 43a) reveals that it is possible to be read as follows: "One may not move an egg... in order to rest a bench on it." That is, resting a bench on it is permitted, but moving it in order to get it into position is prohibited.
The RASHBA here also permits one to derive pleasure from an object that is Muktzah, but he adds that there is an exception to this allowance. One may not derive pleasure from Muktzah when physical contact with the object of Muktzah is involved. For this reason, he explains, it is prohibited to rest a bench on an egg of Muktzah. This is why lighting the wick of Muktzah is prohibited -- one derives pleasure from the wick at the same moment that he touches it. When he is not touching it, however, he may derive pleasure from the flame even though the wick is Muktzah.

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