1) SLAUGHTERING A GRANDMOTHER ANIMAL, A MOTHER ANIMAL, AND A CHILD ANIMAL ON THE SAME DAY
OPINIONS: In the Mishnah (14b), Rebbi Yochanan ben Nuri says that one is Chayav three times for having relations with Chamoso (his mother-in-law) who is also Em Chamoso (the mother of his mother-in-law) and Em Chamav (the mother of his father-in-law; that is, a man is married to a woman, and to her sister's daughter, and to her brother's daughter, and he has relations with his first wife's mother). The Chachamim argue and say that they are all one "Shem Isur," and thus he is Chayav only once.
The Gemara suggests that Rebbi Yochanan ben Nuri agrees with the ruling of Sumchus, as recorded in the Mishnah in Chulin (82a). The Mishnah there teaches that one who slaughters an animal (the grandmother), and then its grandchild, and then its child (the mother) on the same day receives only one set of Malkus, according to the Chachamim. (RASHI there (DH Sofeg) explains that this is because he transgressed only one prohibition of "Oso v'Es Beno" with only one Hasra'ah, and through only one action.) Sumchus argues and maintains that he is punished with two sets of Malkus. The Gemara there (82b, and Rashi DH b'He'elem) explains that Sumchus maintains that even though there was only one Hasra'ah and only one Isur, since the Isur was transgressed two times (the grandmother and the mother were slaughtered on the same day, and the mother and the child were slaughtered on the same day), the person receives two sets of Malkus. (See Insights to Chulin 82:3.)
The Gemara rejects the suggestion that Rebbi Yochanan ben Nuri and Sumchus are saying the same thing. Rava says that in the Mishnah here, perhaps Rebbi Yochanan ben Nuri obligates the person for each Isur because they are "Shemos Muchlakim," different Isurim (Chamoso, Em Chamoso, and Em Chamav), but in the case in Chulin, there is only one Isur (Oso v'Es Beno).
Rav Nachman bar Yitzchak rejects the comparison for a different reason. In the case in Chulin, Sumchus obligates the person twice because the animals are "Gufin Muchlakin," separate entities. Here, though, there is only one woman with whom the man is transgressing. Perhaps here Sumchus would not say that one is Chayav multiple Chata'os, since there is only one Guf (the woman) with which he transgresses the multiple Isurim.
What, though, is the difference between the case of Sumchus and the case of the Mishnah here? In both cases, the multiple Isurim are being done with only one object! In the case of Sumchus, the two Isurim are being committed by slaughtering the animal which is the daughter of the first animal that was slaughtered that day, and which is the mother of the second animal that was slaughtered that day. Similarly, in the case of the Mishnah here, the three Isurim are being committed by having relations with one woman, who is both the man's mother-in-law (she is the mother of his first wife) and the mother of the man's mother-in-law (she is the grandmother of his second and third wives). If the case of Sumchus is considered a case of Gufin Muchlakin because different animals cause each Isur, then the case here also should be considered a case of Gufin Muchlakin, because the man's relationships with different women cause each Isur.
ANSWER: The MAYIM KEDOSHIM explains that the Isur of Oso v'Es Beno (in the case of Sumchus) differs from the Isurim of Arayos in a fundamental way. The Isur of Oso v'Es Beno forbids slaughtering both the mother and her daughter on the same day. The Torah does not prohibit slaughtering the daughter alone, on the day on which the mother happened to be slaughtered. Rather, the Torah prohibits slaughtering the mother and daughter together on the same day. Consequently, one transgresses two Isurim of Oso v'Es Beno by slaughtering the grandmother animal, the grandchild animal, and then the mother animal on the same day, since two sets of mother-daughter animals have been slaughtered.
In contrast, when the Torah prohibits marrying one's mother-in-law, the Isur is not, "Do not marry a woman and her mother at the same time," but rather the Isur is, "Do not marry the daughter (or mother) of your wife." Consequently, the fact that one woman became forbidden to him as a result of relationships he has with multiple women does not give the Isurim the status of Gufin Muchlakin. The Isurim involve only this woman (his mother-in-law, who is also the mother of his mother-in-law), and she is not Gufin Muchlakin.
The Mayim Kedoshim uses this difference to question the words of the TOSFOS YESHANIM (DH Ad Kan), who says that one who is married to two women who are unrelated to each other but who are both half-sisters to a third a woman (one from the father, and one from the mother) is Chayav twice if he marries the third woman, according to Sumchus. This is considered Gufin Muchlakin since two separate wives of his cause the two Isurim of the third woman.
The Mayim Kedoshim asks that Tosfos' case of Achos Ishah should be the same as the case of the Mishnah here; even though two women cause the third woman to have two Isurim on her, the Isurim involve only the third woman ("do not marry your wife's sister"), and it should not be considered a case of Gufin Muchlakin! The Mayim Kedoshim leaves this question unanswered. (Indeed, RAV SHACH zt'l in AVI EZRI (Hilchos Shegagos 4:4) says that the words of the Tosfos Yeshanim here are a printer's error.)
(Perhaps one may suggest that the wording of the Torah implies that, indeed, in the case of Achos Ishah, the Isur is, "Do not marry two sisters together" (like the Isur of Oso v'Es Beno) and not just, "Do not marry the sister of your wife." The Torah says, "A woman as well as her sister do not marry, to make them quarrel (li'Tzeror)" (Vayikra 18:18), which implies that the Torah prohibits being married to two sisters at once, which will "make them quarrel." Consequently, in the case of the Tosfos Yeshanim, when the man who is married to the two half-sisters of the third woman marries the third woman, the Isur indeed is committed with Gufin Muchlakin, since he is married to his first wife and her sister, and married to his second wife and her sister.) (Mordechai Zvi Dicker)
2) REBBI AKIVA'S CASE OF A TRIPLE "ERVAH"
QUESTION: The Mishnah quotes Rebbi Akiva who says, "I asked Raban Gamliel and Rebbi Yehoshua... about a case of one who has relations with his sister, his father's sister, and his mother's sister. Is he Chayav for each, or is he Chayav only once for all of them?" The Gemara explains that Rebbi Akiva was asking about a case in which a man has relations with his sister, who is also his father's sister and his mother's sister. Is he obligated to bring a Korban for each Isur that he transgressed (and in this case he transgressed three Isurim: Achoso, Achos Aviv, and Achos Imo), or is he obligated to bring a Korban for each woman with whom he transgressed (and in this case he transgressed with only one woman)?
Why does Rebbi Akiva ask this question only in this rare and odd case, which could exist only with a Rasha ben Rasha, and in which there are only three Isurim on one woman and not more? Rebbi Akiva should have asked the same question with regard to all of the cases of the previous Mishnayos, in which one who has relations with one woman can be Chayav for six, seven, or eight Chata'os, since she is prohibited to him as a result of numerous Isurim. (M. KORNFELD)
ANSWERS:
(a) Perhaps Rebbi Akiva asks his question only with regard to this case because he was concerned that Raban Gamliel and Rebbi Yehoshua might not agree with the concepts of Isur Mosif and Isur Kolel. Therefore, he asks his question with regard to a case in which there are three Isurim that take effect at one time (b'Vas Achas), without having to rely on the concepts of Isur Mosif or Isur Kolel for the multiple Isurim to take effect. (M. KORNFELD)
(b) Perhaps Rebbi Akiva asks his question only with regard to this case because the case of Achoso is a greater Chidush than the cases of the previous Mishnayos. (That is, even in such a case, one could be Chayav to bring three Chata'os for sinning with just one woman.) In the case of Achoso, all of the Isurim stem from the same category of Isur -- the category of "Achvah" (siblinghood). Consequently, one might have thought that one would not be Chayav to bring three Chata'os for these three Isurim, while in the cases of the previous Mishnayos -- in which the woman is prohibited by Isurim that do not all stem from the same category -- he would be Chayav to bring multiple Chata'os. Rashi earlier (2b, DH Al Achoso) refers to the category of siblinghood, and Rabeinu Gershom here also makes reference to it. In the cases of the other Mishnayos, the Isurim are all different categories of Isur, and thus perhaps only in those cases the Bo'el would be Chayav to bring a Chatas for each one.
3) "IN THE BUTCHERY OF IMA'UM"
QUESTION: The Mishnah quotes Rebbi Akiva who says, "I asked Raban Gamliel and Rebbi Yehoshua in the butchery of Ima'um, when they went to buy an animal for the wedding party of the son of Raban Gamliel, regarding a case of one who has relations with his sister, his father's sister, and his mother's sister. Is he Chayav for each, or is he Chayav only once for all of them?"
Why does the Mishnah mention that Rebbi Akiva asked his teachers this question "in the butchery of Ima'um, when they went to buy an animal for the wedding party of the son of Raban Gamliel"? What relevance does this detail have to the law of the Mishnah? (TOSFOS YESHANIM)
ANSWERS:
(a) The TOSFOS YESHANIM answers that the Mishnah is teaching that wherever a Talmid Chacham is, and whatever he is doing, he never removes his mind from the Torah.
(b) The MAHARSHAM (in Hagahos ha'Shas) answers this question based on the words of the Midrash. The Midrash (Koheles Rabah 7:7) relates that Rebbi Elazar Ben Arach forgot all of his learning because he partook of the physical pleasures of "Ein Ma'um" (see Shabbos 147b). The Mishnah here teaches that even though Rebbi Akiva and his teachers needed to travel to Ima'um (the same place as Ein Ma'um) to purchase an animal for a wedding celebration, they were careful to speak in Torah throughout their journey, in order to avoid succumbing to the material atmosphere of the place.

15b----------------------------------------15b

4) THE "CHUMRA" OF "TAMCHUYIN MECHALKIN"
QUESTION: Rebbi Akiva says that although with regard to Me'ilah, Tamchuyin are Mechalkin the Isurim and one is Chayav Malkus for each Tamchuy, this stringency does not exist for other Isurim.
The SEFAS EMES asks that the Gemara here seems to contradict the Gemara earlier (12b). The Gemara there (in its second version) says that Tamchuyin are Mechalkin both l'Kula (to be lenient) and l'Chumra (to be stringent). That is, the concept of Tamchuyin Mechalkin is not only a Chumra to be Mechayev a person to bring two Chata'os for eating two Shi'urim from two dishes, but it is also a Kula for one who ate one Shi'ur from two dishes together. Since the Tamchuyin are Mechalkin, one is not considered to have eaten a Shi'ur of Isur, and he is exempt.
This contradicts the Gemara here, in which Rebbi Akiva argues with Rebbi Yehoshua and says that Tamchuyin Mechalkin is true only with regard to Me'ilah, because Me'ilah is more severe than other Isurim. However, the Gemara earlier says that Tamchuyin Mechalkin is also a Kula, and thus the fact that Me'ilah is more severe is not a reason to apply Tamchuyin Mechalkin to it more than to any other Isur!
ANSWER: The SEFAS EMES answers that it must be that Rebbi Akiva understands that Rebbi Yehoshua learned the concept of Tamchuyin Mechalkin from his teachers, but his teachers did not explain whether it is only l'Chumra or also l'Kula. The Gemara earlier (12b) says that Rebbi Yehoshua (at least before Rebbi Akiva argued with him) maintains that the concept of Tamchuyin Mechalkin applies both l'Chumra and l'Kula. According to Rebbi Yehoshua, the concept of Tamchuyin Mechalkin definitely applies to other Isurim, and not only to Me'ilah. Since Tamchuyin Mechalkin is also a Kula, as explained above, the application of the concept cannot be attributed to a Chumra unique to Me'ilah.
Rebbi Akiva argues with Rebbi Yehoshua on this point. Rebbi Akiva maintains that Rebbi Yehoshua's teachers did not mean that Tamchuyin Mechalkin creates a leniency. Rather, they taught only that Tamchuyin Mechalkin creates a Chumra by being Mechayev a person who ate two Shi'urim from two dishes to bring two separate Korbanos. One who eats one Shi'ur from two dishes, however, remains Chayav to bring just one Chatas.
Since Tamchuyin Mechalkin is only a Chumra, Rebbi Akiva concludes that Tamchuyin Mechalkin applies only to Me'ilah, because Me'ilah is more severe than other Isurim.
(The Sefas Emes is in doubt about the law in the following case. One ate half of a Shi'ur of Isur from each of four dishes of Hekdesh. How many times is he Chayav? Perhaps Tamchuyin Mechalkin applies, and he is Chayav only twice. The fact that he ate only half of a Shi'ur from each dish does not prevent him from being Chayav, because Tamchuyin Mechalkin does not apply to be lenient (l'Kula). On the other hand, to apply Tamchuyin Mechalkin here in order to make him Chayav would be inherently contradictory, because the only way for him to be Chayav for eating a Shi'ur of Isur is for the Tamchuyin not to be Mechalkin. Perhaps, then, one is Chayav only once for eating half a Shi'ur from four different dishes.) (Mordechai Zvi Dicker)
It seems that the question of the Sefas Emes may be answered in a simple way. Even if Rebbi Yehoshua's law of Tamchuyin Mechalkin is said both l'Kula and l'Chumra, the Kula is an outcome of the Chumra. Since one would be obligated to bring a Korban for each Shi'ur if there would be a Shi'ur of Isur in both Tamchuyin, the two Tamchuyin cannot join to be Mechayev him. This is understandable, since in truth the Tamchuyin do not turn the two pieces into two separate Aveiros; they merely separate the acts of the Aveirah in order to obligate him to bring more than one Korban. Nevertheless, a law in the Halachos of Korbanos states that if two acts can obligate two Korbanos, they cannot join to obligate one Korban (see RASHI to Shabbos 71a, DH Chalukin). Since the Kula is only an outcome of the Chumra, the words of Rebbi Akiva are clear. The law of Tamchuyin Mechalkin is a Chumra, and thus one cannot learn from there to more lenient Isurim. Although there are also Kula repercussions, those repercussions do not change the Tamchuyin Mechalkin into a law which can be applied in all places.

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