1) YOM TOV THAT FOLLOWS SHABBOS
QUESTION: The Gemara discusses whether Shabbos and Yom Tov that occur on two consecutive days are considered to be two separate Kedushos or one long Kedushah. Rebbi Eliezer maintains that the two days are two separate Kedushos, while the Chachamim maintain that the two days are one long Kedushah. The Halachah follows the opinion of Rebbi Eliezer.
An important Halachic question arises according to the opinion of the Chachamim. Normally, a person is allowed to slaughter an animal on Yom Tov because it is a Melachah that is done for the sake of food preparation (Ochel Nefesh). On Shabbos, of course, the animal is Muktzah because it is forbidden to slaughter on Shabbos. What is the Halachah when Yom Tov immediately follows Shabbos? If two consecutive days of Shabbos and Yom Tov are considered one Kedushah, what is the status of an animal on the Yom Tov that follows Shabbos? Is the animal Muktzah on Yom Tov due to the fact that it was Muktzah at the beginning of Shabbos? Does it remain Muktzah throughout the duration of the entire Kedushah or is there another option?
ANSWERS:
(a) The RAN in Beitzah (2a) writes that according to the Chachamim, an animal is Muktzah on a Yom Tov that immediately follows Shabbos. On that Yom Tov, it is forbidden to slaughter an animal.
(b) The RAMBAN (in Milchamos, Beitzah 31b) asserts that the Chachamim agree that one may slaughter an animal on a Yom Tov that immediately follows Shabbos. His reasoning is as follows.
An animal is Muktzah on Shabbos because it cannot be slaughtered and turned into an edible product. This type of Muktzah is called "Muktzah Machmas Isur" -- a prohibition prevents use of the object on Shabbos. (In this case, it is the prohibition of Shechitah that prevents use of the animal on Shabbos.) In such a situation, the object itself does not become inherently Muktzah. Rather, the object is Muktzah only because of the prohibition that prevents it from being used. As soon as the prohibition is removed, the object becomes permitted (even on the same Shabbos). Therefore, on Yom Tov that occurs after Shabbos, the animal becomes permitted as soon as Shabbos departs and there is no longer a prohibition of Shechitah,.
(This approach seems to be contradicted by the law in Shabbos (42b, 44a) that oil that drips from a candle on Shabbos remains Muktzah even after the candle is extinguished. The oil was Muktzah Machmas Isur because the prohibition of extinguishing made it forbidden to be handled at the beginning of Shabbos. Nevertheless, it remains Muktzah for the duration of Shabbos, even when the prohibition of extinguishing no longer applies (because the candle became extinguished by itself). Perhaps the Ramban understands that, in such a case, the oil is also forbidden because the person specifically decided not to use it. That is, when he lit the candle before Shabbos, it was with specific intent not to use the oil at all on Shabbos. He "pushed it out of his mind" and thereby made the oil Muktzah for the duration of Shabbos.)
(c) The OR SAME'ACH (Hilchos Yom Tov 1:19) suggests that even if two consecutive days of Shabbos and Yom Tov are one Kedushah, this Kedushah applies only to laws that are common to both Shabbos and Yom Tov (such as the laws of Eruv Techumin). With regard to laws that apply only on Shabbos, though, such as Muktzah due to the prohibition of Shechitah, Shabbos and Yom Tov are not one Kedushah. Rather, they are two separate Kedushos, because the prohibition of Shechitah applies on Shabbos and not on Yom Tov.

38b----------------------------------------38b

2) WHEN THE ERUV BECOMES EFFECTIVE
QUESTION: Rabah says that while the Eruv takes effect at the beginning of the day (the onset of Shabbos; "Techilas ha'Yom Koneh Eruv"), nevertheless, it must be edible at the last moment of the preceding day ("Ra'uy le'Echol mib'Od Yom"). Abaye argues and says that the Eruv takes effect at the end of the day (Friday, before sundown; "Sof ha'Yom Koneh Eruv"), and it does not need to be edible during the day.
Abaye challenges Rabah's ruling that the Eruv must be fit to be eaten during the preceding day. In the Mishnah (38a), Rebbi Eliezer says that one who made an Eruv to the east on the first day of Yom Tov (2000 Amos to the east) may make an Eruv to the west (2000 Amos to the west) on the next day, which is Shabbos. If the Eruv must be fit to be eaten during the day, why is such an Eruv valid? During the day (the last few moments of Yom Tov), the new Eruv is 4000 Amos away from one's present Makom Shevisah. Since one is forbidden to walk more than 2000 Amos on Yom Tov, he cannot possibly reach the new Eruv.
Why does Abaye ask this question only on Rabah's ruling? The same question applies to Abaye's own ruling. Abaye maintains that the Eruv takes effect at the end of the day, and thus he certainly agrees that the Eruv must be accessible at the time that it takes effect, before the onset of Shabbos. Since the Eruv is 4000 Amos away from his present Makom Shevisah at the time that it takes effect, it should not be valid. (As the Mishnah (35a) states clearly, one's Eruv must be within his Techum.) Why, then, even according to Abaye, does Rebbi Eliezer say that such an Eruv is valid? (TOSFOS DH v'Ha Ba'inan; Tosfos leaves this question unanswered.)
ANSWERS:
(a) The RITVA suggests that just as Abaye does not require the Eruv to be fit to be eaten during the day, he also does not require that one's Eruv be within 2000 Amos of his present Makom Shevisah. Rather, as long as the Eruv is within 2000 Amos of one's city, it is valid. Here, after the new Eruv takes effect, the person will be located within 2000 Amos of that new Eruv.
In contrast, Rabah -- who maintains that the Eruv must be fit to be eaten even before the onset of Shabbos -- also requires that the Eruv be within 2000 Amos of his Makom Shevisah before Shabbos starts, and not just within 2000 Amos of his physical position when the Eruv takes effect.
(b) TOSFOS RABEINU PERETZ suggests that if the Eruv takes effect at the end of the day (before Shabbos or Yom Tov), then it is operative only until the end of the day. In other words, two things occur at the end of the first day of Yom Tov. One, the first Eruv becomes inoperative, and two, the new Eruv becomes operative. As a result, one's Makom Shevisah transfers to the location of the new Eruv even before the next day starts. The new place is not considered to be outside of his old Makom Shevisah because he has already lost that Makom Shevisah.
However, according to Rabah (who says that the Eruv takes effect at the beginning of the day), the Makom Shevisah created by the Eruv remains in effect until the very end of the first day. Consequently, his new Eruv is not within his Makom Shevisah before the second day starts. Since the Eruv must be fit to be eaten before the day starts, it must also be in his Makom Shevisah during that day as well. (This is also the answer of the GA'ON YAKOV.)

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