1) WHAT OILS MAY BE USED FOR THE SHABBOS LIGHTS
QUESTION: The Beraisa lists a number of opinions concerning what materials may be used for kindling lights for Shabbos. Rebbi Tarfon says that one may use only olive oil. Rebbi Yochanan ben Nuri says that one may use all oils except those mentioned by the Chachamim in the Mishnah (20b). Rebbi Shimon Shezuri says that one may use the oil of Paku'os (a type of gourd) and Neft (naphta, which is distilled coal, tar, or petroleum).
In what way is Rebbi Shimon Shezuri arguing with the previous Tana, Rebbi Yochanan ben Nuri? He cannot mean that only these two materials may be used, because these two are inferior to other oils, as is evident from the Mishnah. If these may be used, then certainly other oils may be used. He cannot mean even these two materials may be used, because Rebbi Yochanan ben Nuri already said that one may use any materials not prohibited by the earlier Mishnah, and thus these two may be used!
ANSWERS:
(a) TOSFOS in Chulin (75b, DH Ana) and the RITVA explain that Rebbi Shimon Shezuri indeed maintains that these two materials are the only ones with which one may light. This, however, does not mean that all other materials (even better oils) are prohibited. Rather, of all of the inferior oils that Rebbi Yochanan permits, Rebbi Shimon Shezuri permits only these two.
(b) TOSFOS (DH Rebbi Shimon Shezuri) mentions an alternate reading in the Gemara, according to which the text is, "Rebbi Shimon Shezuri says we do not light with oil of Paku'os and Neft." While Rebbi Yochanan ben Nuri permits these two, Rebbi Shimon Shezuri (according to this text) prohibits them because they have a bad smell, but he permits the other oils. (This approach is the exact opposite of the previous explanation, that of Tosfos in Chulin and the Ritva.)
(c) The TOSFOS HA'ROSH answers that when Rebbi Yochanan ben Nuri says that one may use any oil not mentioned in the Mishnah, he is not permitting the oil of Paku'os and Neft, even though these two are not mentioned in the Mishnah. (Although he cites the practice of the people of Kapotkia who light with Neft, in that statement he is referring to black Neft, which he permits. He prohibits using white Neft. Rebbi Shimon Shezuri permits even white Neft.)
How do we know that Rebbi Yochanan ben Nuri does not permit the oil of Paku'os and Neft, even though he says that all oils not mentioned in the Mishnah are permitted? The Rosh explains as follows. Once Rebbi Yochanan has said that one may light with all oils that are not listed in the Mishnah, why does he add, "And one may light with the oil of fish and with Itran"? If he has already said that all oils not listed in the Mishnah are permitted, he does not need to say that these two oils are permitted! It must be that when Rebbi Yochanan ben Nuri says that all oils are permitted, he does not mean literally all oils, but rather all oils that are permitted by tradition (such as the ones which he specifically mentions). Oil of fish and Itran, however, may be used even though there is no tradition that permits their use.
Since Rebbi Yochanan ben Nuri does not permit all oils, it is possible that he indeed prohibits the use of the oil of Paku'os and Neft (white Neft). Rebbi Shimon Shezuri, then, permits lighting with the oil of Paku'os and white Neft.
The RASH MI'SHANTZ challenges this explanation, because the words of Rebbi Yochanan ben Nuri clearly imply that all other oils are permitted (including the two that Rebbi Shimon Shezuri mentions).
In response to the question of the Rash mi'Shantz, we may suggest that when Rebbi Yochanan ben Nuri says "all oils," he is referring only to oils that one may not use because they do not burn well (and the Rabanan were concerned that one might tilt the lamp on Shabbos). Perhaps he agrees, though, that there are other oils that may not be used for other reasons (such as oils that have a bad smell). This is why he adds that the oil of fish and Itran may be used, even though they have a bad smell. He might agree, though, that there are other oils which are prohibited for a third reason (such as oils that have a nice smell, like white Neft, in which case the Rabanan were concerned that one might take some oil out of the lamp). Rebbi Shimon Shezuri means to permit even those oils. (M. KORNFELD)
2) INTRODUCTION: GARMENTS BECOMING "TAMEI"
(a) Two categories of garments: The Gemara discusses the Tum'ah of small pieces of garments, including when they are able to become Tamei and when they are not. These small pieces of garments are divided into two categories: 1. pieces that are "Shalosh Al Shalosh Etzba'os" (three by three fingerbreadths), and 2. "Sheloshah Al Sheloshah Tefachim" (three by three handbreadths). (The Gemara uses the masculine word for three, "Sheloshah," to refer to "Tefachim," a masculine noun, and the feminine form for three, "Shalosh," to refer to "Etzba'os," a feminine noun. Generally, wherever the abbreviation "Gimel" appears in the Gemara and Rishonim in this Sugya, it represents the feminine "Shalosh").
The difference between these two categories of garments is that if a garment is only three by three Etzba'os, then it is useful only for a poor person who hoards even small scraps of material to use. If it is three by three Tefachim, then even rich people find it useful and keep it.
(b) Two categories of Tum'ah: There are two general categories of Tum'ah: 1. Tum'as Nega'im (this refers to a garment upon which green or red spots appear, which are classified as Nig'ei Begadim, an affliction of Tzara'as that affects a garment), and 2. all other Tum'os (Tum'as Mes, Tum'as Sheretz, etc.).
The Mishnah in Nega'im (11:2) teaches that only garments made of wool (Tzemer) or flax (Pishtim) can become Tamei with Tum'as Nega'im. Everyone agrees with this law.
Regarding the other types of Tum'os, there are differing opinions whether only wool and flax can become Tamei or other materials can also become Tamei. Some maintain that other materials cannot become Tamei with such Tum'os, just as they cannot become Tamei with Tum'as Nega'im. Others maintain that they can become Tamei, but only when they are three by three Tefachim, and not when they are merely three by three Etzba'os. Others maintain that even when they are three by three Etzba'os they can become Tamei. (See Chart #6.)

26b----------------------------------------26b

3) THE SOURCE FOR A SMALL GARMENT BECOMING "TAMEI"
QUESTION: The Gemara says that we learn that a garment of wool or flax which is only three by three Etzba'os in size can become Tamei from the word "veha'Beged" (Vayikra 13:47). The Gemara asks that perhaps this word is intended to teach that a garment of other materials that is three by three Tefachim can become Tamei, and that a wool or flax garment of three by three Etzba'os is derived from another source. From what other source does the Gemara intend that it be derived?
ANSWERS:
(a) RASHI (DH v'Eima l'Rabos and DH v'Eima Ki) says that it would be derived from the Kal v'Chomer from "Shesi va'Erev" that the Gemara suggested earlier and refuted.
(b) TOSFOS (DH v'Eima l'Rabos) disagrees, because the Gemara just said that the Kal v'Chomer cannot teach that a garment of three by three Etzba'os becomes Tamei. Tosfos therefore explains that since the verse specifically mentions "Tzemer" and "Pishtim," thereby limiting Tum'as Nega'im to garments made of wool and flax, it must be that they have some law that other materials do not have. Consequently, if "veha'Beged" teaches that other materials of three by three Tefachim can become Tamei, then it must be that wool and flax can become Tamei even when they are only three by three Etzba'os.
To defend Rashi's explanation, we may suggest that perhaps Rashi understands that the Gemara earlier was unsure whether the Kal v'Chomer from "Shesi va'Erev" to garments of three by three Etzba'os is a workable Kal v'Chomer. Even though the Gemara refutes the Kal v'Chomer by saying that "Shesi va'Erev" is more of a completed garment than one which is only three by three Etzba'os, the Gemara makes that statement only because the word "veha'Beged" ostensibly teaches us not to make the Kal v'Chomer. However, the Gemara may still be in doubt about whether "Shesi va'Erev" is less of a garment than one which is three by three Etzba'os (because at least the small garment is fit for a poor person's use, while "Shesi va'Erev" cannot be used even by a poor person), and if the word "veha'Beged" can be used to teach something else, then the Kal v'Chomer will work. (M. KORNFELD)

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