1) A CONVERT WHO MARRIES "ISHAH U'VITAH"
OPINIONS: The Gemara quotes a Beraisa which discusses exactly whom a Ger is forbidden from marrying. The main reason why a Ger differs from an ordinary Jew in this regard is his status of "k'Katan she'Nolad" -- he is "like a newborn child" after he converts. According to the Torah, he no longer is deemed related to any of his former relatives. However, the Rabanan prohibited him from marrying some of his former relatives.
One case in the Beraisa discusses a convert who marries a woman and her daughter ("Ishah u'Vitah"). The Beraisa says that he should marry one and divorce one.
What are the details of the Beraisa's case?
(a) RASHI (DH Nasa Ishah u'Vitah) writes that the case involves a Ger who married a woman and her daughter before he converted, and they all converted together. The Halachah is that he cannot maintain the two marriages, even though the woman and her daughter are no longer considered related to each other according to Torah law. He therefore may choose to marry one and divorce the other.
(b) Alternatively, Rashi explains that the case is not talking specifically about a Ger, but it refers to any Jew who marries a mother and daughter who converted. Although the woman and her daughter are no longer considered related to each other according to Torah law, the Rabanan did not allow him to marry women converts who were a mother and daughter before they converted.
TOSFOS in Yevamos (98b, DH Nasa Ishah u'Vitah) says that the first explanation of Rashi is correct. If the Beraisa's case refers to any Jew, the Kidushin which the Jew performed takes effect for both women since, according to Torah law, both are permitted to him. The Gemara should therefore say instead, "Yekayem Achas" -- "he may keep one of them," and not "Kones Achas" -- "he marries (lit. gathers in) one of them." The word "Kones" implies that he is Mekadesh one of them, which he would not have to do if he already married both of them. He simply must divorce one of them.
Alternatively, instead of saying "Yekayem Achas u'Motzi Achas," the Beraisa should have said merely "Motzi Achas" -- "he must divorce one of them." However, according to the first explanation, the case of "Nasa Ishah u'Vitah" refers to the fact that they got married when they were Nochrim. After they are married, Beis Din tells him to be "Kones Achas u'Motzi Achas" -- "he marries one and divorces one." Tosfos therefore says that this explanation of the Gemara is correct.
However, the RAMBAM (Hilchos Isurei Bi'ah 14:15) and the SHULCHAN ARUCH (YD 269:5) both describe the verdict of the case as, "He stays with one of them and divorces the second." This implies that they learn the Gemara like the second explanation of Rashi, that no real act of marriage is required because both marriages are already valid. Why then, as Tosfos asks, does the Gemara say "Kones Achas"?
1. The CHIDUSHIM U'VI'URIM answers that it is possible that the Rambam and Shulchan Aruch understand the phrase "Kones Achas" as not necessarily referring to a new act of marriage, but merely as a statement that they may remain married. In this context, the word "Kones" is used like the word "Yekayem."
2. Alternatively, the Chidushim u'Vi'urim suggests that the Rambam and Shulchan Aruch indeed learned the Gemara like the second explanation of Rashi. However, the Rambam (and Shulchan Aruch after him) merely applied this Halachah to the case of a Yisrael as well to that of a Ger. Presumably, they maintain that there is no Halachic difference between the two cases. In this manner, the Halachah is also stated with regard to a Jew, and not only a Ger. (Y. MONTROSE)

58b----------------------------------------58b

2) WHY WAS AVRAHAM AVINU PERMITTED TO OBSERVE SHABBOS?
QUESTION: The Gemara teaches that a Ben Noach may not observe Shabbos, as it derives from the verse, "v'Yom va'Lailah Lo Yishbosu" - "and day and night shall not cease [to function in their natural order, as they ceased during the Flood]" (Bereishis 8:22). The Gemara interprets this phrase to mean, "and [for a period of] day and night [people] shall not cease [to work productively]."
The commentators ask that this teaching seems to contradict the Gemara in Yoma (28b) which states that Avraham Avinu observed all of the Mitzvos of the Torah, even before the Torah was given. How could Avraham Avinu, who was a Ben Noach, observe Shabbos, if a Ben Noach who observes Shabbos is Chayav Misah?
ANSWERS:
(a) The HAFLA'AH in PANIM YAFOS explains that before the Torah was given, the new day began with daybreak. In contrast, after the Torah was given, for the Jewish people the new day begins at nightfall. Accordingly, when Avraham Avinu observed Shabbos, he observed the Jewish day, which began at nightfall on Friday evening and ended at the following nightfall, the way the Jewish people observe Shabbos today. He was not Chayav Misah because he performed work on Friday morning and on Saturday night, and thus he did not observe the Ben Noach's day as Shabbos. It is clear (according to the Hafla'ah) that a Nochri's prohibition against observing Shabbos applies to the Nochri's day, which begins at daybreak, as the verse says "v'Yom va'Lailah" -- "and day and night," implying that the Nochri is prohibited from resting from Melachah from Saturday morning through Saturday night, until daybreak on Sunday.
(b) Perhaps another answer may be suggested based on a more thorough analysis of the Gemara. Ravina says that even a Nochri who refrains from Melachah on Monday is Chayav Misah. What is the reason behind Ravina's opinion?
1. RASHI (DH Amar Ravina) explains that the Torah prohibits a Nochri "from having a day of rest, that they should not stop working." Rashi apparently understands that the Nochrim are supposed to keep the world in working order so that the Jewish people can do what they are supposed to do -- be constantly devoted in every aspect of their lives to the service of Hash-m. This idea is illustrated by the Gemara in Avodah Zarah (40b). The Gemara there relates that Rebbi was sick and needed aged apple wine to cure his ailment. There was one Nochri who owned three hundred barrels of this rare wine. After Rebbi consumed some of the wine and was cured, he exclaimed, "Baruch ha'Makom she'Masar Olamo l'Shomrim" -- "Blessed is Hash-m who gave over His world to watchmen." The HA'BONEH in the EIN YAKOV to Avodah Zarah comments that Rebbi was praising Hash-m for ensuring that there would be people involved in all aspects of productivity in the world so that when the Jewish people are in need of those things, they are available.
The Nochrim are obligated to observe the seven Mitzvos of Bnei Noach, which the Gemara calls negative commandments. (Although one of those Mitzvos, establishing a system of courts and law, seems to be a positive commandment, its purpose is to prevent people from committing evil actions. See 59a and Rashi DH Kum Aseh.) If the Nochrim fulfill their Mitzvos and properly fulfill their role in the world, they will receive eternal reward in Olam ha'Ba. However, if they choose to transgress Hash-m's seven basic Mitzvos for humanity and insist on hindering, rather than helping, the progress of the world, their existence in the world is rendered unnecessary and thus they are Chayav Misah. Accordingly, they may not desist from working for an entire day, since their role is to maintain the productivity of the world. (For a different understanding of Rashi's words, see TORAH TEMIMAH to Bereishis 8:22.)
2. The RAMBAM (Hilchos Melachim 10:9) writes that the nature of this prohibition is that "we do not let them make a new religion and to make up their own Mitzvos. Rather, he (the Nochri) should either become a righteous convert and observe all of the Mitzvos, or he should uphold his laws (the seven Mitzvos of Bnei Noach) and not add to or subtract from them."
What is the Rambam's source for explaining that the Gemara here means that the Nochrim should not "make a new religion" with "their own Mitzvos"?
To better understand the Rambam, some basic questions on the verses, among which the verse of "Lo Yishbosu" appears, need to be asked. Noach understood that Hash-m wanted him to offer Korbanos when he emerged from the Teivah, from the fact that Hash-m had told him to take seven pairs of the kosher species of animals (see Bereishis 8:21 and Rashi there). Noach's actions found favor in the eyes of Hash-m, Who then promised that He would no longer destroy the world and declared that if Noach's descendants observe Shabbos they will be Chayav Misah. Hash-m's promise not to destroy the world, in response to Noach's righteous act of offering Korbanos, makes sense. However, in what way was Hash-m's declaration that Noach's descendants would be Chayav Misah for observing Shabbos related to his offering of Korbanos?
Another problem is that the verse itself seems redundant. After Hash-m accepted the "Rei'ach Nicho'ach" of the Korbanos, He said, "I will not continue to curse the land due to man, as the inclination of man is evil from his youth, and I will not continue to smite all living things as I have done" (Bereishis 8:21). (The verse that follows is the prohibition of "Lo Yishbosu.") Why does the verse repeat Hash-m's promise not to destroy the world? The Gemara in Shevuos (36a, see Insights there) answers this question when it derives from the verse a general lesson that one must state an oath twice. However, how does this explanation help understand why Hash-m links this promise to the prohibition against Bnei Noach from observing Shabbos?
Perhaps the verse refers to two types of person. One type, like Noach, dedicates his life to fulfilling the will of Hash-m, sometimes even before Hash-m makes it know that this is His will. This seems to be the verse's reason for why Hash-m promised not to bring another flood to the world.
The second type of person does not want to dedicate his life to serving Hash-m. How is he protected by Hash-m's promise not to destroy the world? The answer is obvious. If he supports those who do dedicate their lives to the service of Hash-m, he also shares in their merit. It is possible that the first part of the verse, which says that Hash-m will not curse the land due to "man" ("Adam"), refers to the Jewish people who are generally referred to as "Adam" (see TOSFOS to 59a, DH Ela ha'Adam). Since their role in the world is to serve Hash-m, Hash-m promises that He will not destroy the world even when they sin. The second part of the verse, which mentions "all living things" ("Kol Chai") refers to Nochrim. They will also not be destroyed, since they are supposed to support and assist the Jewish people's dedication to Hash-m.
This approach provides the reason for why the verse continues with the prohibition of "Lo Yishbosu." This is the condition for the fulfillment of Hash-m's promise not to destroy the nations of the world with a flood. They must be dedicated to building up the world in order to enable the Jewish people to dedicate their lives to Kidush Shem Shamayim. If they do not rest from this task, they share the merit which protects them from another flood. If they rest, however, they are Chayav Misah.
This is the source for the words of the Rambam that the Nochrim should not "make a new religion" with "their own Mitzvos." There are two reasons for why a person may merit Hash-m's protection to be protected from destruction: he devotes his life to Hash-m, or he builds a world that assists those who do. He cannot create a third category: those who work but also rest, for such a category is not included in those who are protected from a flood. This is why the Rambam says that one must be either a full-fledged Jew or a Nochri. There is nothing in between.
This may also explain the Rambam's statement there that although a Nochri who observes Shabbos is Chayav Misah, Beis Din does not kill a Nochri who observes Shabbos, unlike one who transgresses any of the seven Mitzvos of Bnei Noach. This is because his Chiyuv Misah is due to the fact that he does is not in any of the categories of people who are saved from destruction. The punishment is from Hash-m, not from Beis Din.
This also answers the original question: why was Avraham Avinu permitted to observe Shabbos? According to this approach, Noach and Avraham were not included in the prohibition of "Lo Yishbosu" because they were in the first category of people -- those who dedicate their lives to serving Hash-m. They therefore were not prohibited from observing Shabbos in the normal manner. (However, this exemption applies only before the Torah was given, before Hash-m clearly distinguished between Nochrim and Bnei Yisrael. Today a person who is born a Nochri has only one of two options, as stated by the Rambam.) (Y. MONTROSE)

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