ANSWERS TO REVIEW QUESTIONS
prepared by Rabbi Eliezer Chrysler of Kollel Iyun Hadaf, Yerushalayim
Rosh Kollel: Rabbi Mordecai Kornfeld
(a) Rebbi Eliezer permits a person to place two Eruvin, one to the east and one to the west, the one to be effective on the Yom-Tov, the other, on the Shabbos that follows it (or vice-versa) - because he holds that Shabbos and Yom-Tov are two separate sanctities.
(b) The Rabbanan hold that Shabbos and Yom-Tov are the same sanctity. Consequently, one cannot change one's direction from one day to the next - any more than one can in the middle of the day.
(c) No! There is no difference between this case and one in which he places one Eruv and makes a condition to use it on one day, and to retain his regular home as his residence on the other - in either case, Rebbi Eliezer will permit changing from Shabbos to Yom-Tov (or vice-versa), and the Rabbanan will forbid it.
(a) The Rabbanan agree that if the Eruv was eaten in the course of the first day, it is not valid on the second - which would obviously not be the case if the two days shared one sanctity. That is why Rebbi Eliezer asked the Rabbanan in surprise 'But you agree with me that they have two different sanctities?'
(b) The Rabbanan first asked Rebbi Eliezer whether he does not agree with them that one cannot make an Eruv for half a day to the north, and for the second half to the south, even in the same direction (that is what they mean by 'in one direction' - i.e. either one places the Eruv in one direction, or not at all). When he answered in the affirmative, they argued that, in that case, neither can one make an Eruv one day in the east and the next, in the west (which is what they mean by 'two days').
(c) Rebbi Eliezer answers this by saying that, whereas one day comprises only one sanctity (and cannot therefore be divided into two), two days comprise two sanctities, and there is therefore is no reason why one should not be able to divide them into two directions.
(d) Rebbi Eliezer's second proof is from the need to make a new Eruv that one needs to make on foot on the second day (and that one cannot rely on the Eruv that he made on the first day, when he went there before the beginning of Beis Hashemashos) Here too, the Rabbanan conceded this. Does this not prove, he asked them, that even they agreed that Shabbos and Yom-Tov have two different sanctities?
(a) In fact, the Rabbanan were uncertain whether the two days have one sanctity, or two. Consequently, they adopted both opinions Lechumra (which explains why they agreed with both proofs of Rebbi Eliezer, since both were Lechumra).
(b) They go Lechumra both as regards forbidding setting up an Eruv in two directions on the two days (because maybe they comprise one sanctity), and they also go Lechumra to invalidate the Eruv on the second day, if it was eaten on the first (because maybe they comprise two).
(c) According to Rebbi Eliezer, one is not permitted to place an Eruv on Yom-Tov for Shabbos - because of 'Hachanah' (the prohibition of preparing on Yom-Tov for Shabbos or vice-versa, as will be explained on the next Amud).
(a) According to Rebbi, someone who made an Eruv by waiting on the spot of his chosen residence during the first Bein Hashemashos until Shabbos entered , must nevertheless repeat this on the second day. And if his Eruv was eaten on the first day - he may not rely on it to go beyond that point on the second day - The reason for both of these rulings is because Rebbi holds that Shabbos and Yom-Tov, comprise two sanctities (like Rebbi Eliezer).
(b) Rebbi Yehudah holds 'Harei Zeh Chamar Gamal - because he holds like the Rabbanan of Rebbi Eliezer, who are uncertain whether they comprise two sanctities or one. Consequently, he goes Lechumra both ways.
(c) In fact, the Gemara concludes, Raban Shimon ben Gamliel and Rebbi Yishmael the son of Rebbi Yishmael ben Berokah - hold that the two days have two sanctities, like Rebbi, and the Beraisa must be amended to read (after the words of Rebbi) 'and that is also the opinion of Raban Shimon ben Gamliel and Rebbi Yishmael the son of Rebbi Yishmael ben Berokah'.
(a) We rule like Rebbi (and those who follow his opinion), but the author of this opinion is really Rebbi Eliezer.
(b) The reason that, when Rav issued his ruling, he does not also quote Rebbi by name - is because in reality, Rebbi himself only quoted the opinion, without agreeing with it.
(c) Rav had a tradition that Raban Shimon ben Gamliel and Rebbi Yishmael the son of Rebbi Yishmael ben Berokah actually hold that Shabbos and Yom-Tov comprise two sanctities, and were not just quoting it like Rebbi did.
(d) The Gemara refers to Rebbi Yossi b'Rebbi Yehudah as S'timta'ah - because on many occasions, Rebbi concurred with his opinion, and went on to insert it in the Mishnah, in the form of a S'tam Mishnah.
(a) Rabah explains that, although Rav ruled above like Rebbi Eliezer, he nevertheless forbids an egg that was laid on Shabbos, to be eaten Yom-Tov or vice-versa - because of Hachanah, which is forbidden, because the Torah writes in Beshalach "ve'Hechinu es Asher Yavi'u", from which Chazal derive that Shabbos and Yom-Tov must be prepared on a week-day, and not Shabbos on Yom-Tov or vice-versa.
(b) Nevertheless, one may re-place the Eruv on Yom-Tov, to permit going there on Shabbos - because he holds that it is the beginning of the day that acquires the Eruv (i.e. advent of Shabbos), and not the end of Erev Shabbos. Consequently, it is a matter of Shabbos preparing for itself, and not Yom-Tov for Shabbos.
(c) The reason that if he placed the jar of Ma'aser wine (which he has declared Terumas Ma'aser when Shabbos enters) for an Eruv, it is not valid, is because the Eruv must be edible when it is placed, which in this case it is not.
(d) The case when someone places two Eruvin for the two consecutive days, one in the east and one in the west, and which Rebbi Eliezer permits (each Eruv on its respective day) - speaks when the two Eruvin were placed not at the end of the two thousand Amah extremity (in which case the Eruv in the West will not be accessible from the east on the first day, but only at a distance of one thousand Amah on either side, enabling him to go three thousand Amos in each direction, as the Eruv falls due - but which also allow him to go from one Eruv to the other when the first Eruv falls due.
(a) The Gemara initially thinks - that when one makes an Eruv 'on foot' (without food) one is obligated to actually state this verbally for the Eruv to be effective, and, since it is not possible to know exactly when Shabbos comes in, one has no option but to make the statement whilst it is still day (even though we established that, according to Rebbi Eliezer, the beginning of the day acquires the Eruv). So the question arises, how can Rebbi Eliezer permit preparing an Eruv on foot on the first day for the second.
(b) In fact however, Rebbi Eliezer has no problem with this - because the truth of the matter is that it is not necessary to say anything, only to sit at the chosen spot and wait for Shabbos to enter, something that is not called 'Hachanah'.
(c) The Gemara at first thought that Rebbi Eliezer holds like Rebbi Yochanan ben Nuri, who says; with regard to someone who falls asleep whilst waiting at his chosen spot for Shabbos to come in, is nevertheless 'Koneh Shevisah', like property of Hefker, which acquire Shevisah automatically - 'Cheftzei Hefker Konin Shevisah'.
(d) It is possible, the Gemara concludes, that Rebbi Eliezer will even hold like the Rabbanan, who hold that a sleeping person cannot acquire an Eruv - because that is only when he is asleep and is unable to talk; but if he is awake, and is able to talk, even the Rabbanan could agree with Rebbi Eliezer, that since he is able to state that he is Koneh Shevisah, he does not actually need to do so (like the principle of 'Kol ha'Ra'uy le'Bilah, Ein Bilah Me'akeves Bo').
(a) The Beraisa forbids someone to walk around his field on Shabbos to see what needs repairing - because of the Pasuk in Yeshayah "mi'Metzo Cheftzecha".
(b) The Beraisa also forbids someone to go to the gates of the city - in order to be ready, the moment it turns night, to leave the city and go to the bathhouse.
(c) Nevertheless, Rabah, in the name of the Beraisa, permits going as far as the Techum in order to make an Eruv - because it is not evident that he is doing anything untoward, since if he is a Talmid-Chacham, people will say that he is walking around because he is learning. Whereas in the two cases in the Beraisa, since it is obvious why he is walking around his field or waiting by the border, it is forbidden because of Mar'is ha'Ayin.