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Eruvin 36

ERUVIN 36 (15 Sivan) - has been sponsored by David Gerstman in order to support Torah-study, in lieu of a Todah-offering, for miraculously saving him and his brother from harm in a traffic accident (as recommended by the Mishnah Berurah OC 218:32).


QUESTION: The Gemara asks why Rebbi Yosi is lenient with regard to a doubt in Eruv Techumin which is d'Rabanan, but is stringent with regard to a doubt in Tum'ah d'Rabanan. The Gemara answers that Eruv Techumin is a rabbinical enactment that is not based on any d'Oraisa law. Tum'ah d'Rabanan, though, is based on the d'Oraisa laws of Tum'ah.

We find in many Rishonim (see, for example, RIF at end of first chapter of Eruvin, and the RAMBAM, Hilchos Shabbos 27:1, based on the Yerushalmi) that even if we say that Techumin are mid'Rabanan, that refers only to the Halachah of 2000 Amos. However, walking more than 12 Mil (= 12x2,000 Amos) on Shabbos is forbidden mid'Oraisa according to all (since 12 Mil was the size of the encampment of the Jewish people in the wilderness). If so, Eruv Techumin also has a source in the Torah, because there is such a thing as a Techum d'Oraisa! (RASHBA, RITVA)


(a) The RASHBA and MAHARAL (Gur Aryeh, end of first chapter of Eruvin) answers that even though there is such a thing as a Techum d'Oraisa, *Eruvei* Techumin is not based on anything in the Torah. There is no Halachah in the Torah that permits walking beyond the 12 Mil by making an Eruv. Therefore, the laws of Eruvei Techumim indeed cannot have ramifications for a law that is d'Oraisa.

(b) Rav Gedaliah Rabinowitz, zt'l, in GIDULEI HEKDESH, points out that the point of the Rashba and Maharal does not seem to be agreed upon by all. The RAMBAN (Eruvin 17b) writes that if Techumin are d'Oraisa, then Eruv Techumin must also be d'Oraisa (either as a Halachah le'Moshe mi'Sinai or a Sevara). The Ramban adds that according to those who say that the Techum of 12 Mil is d'Oraisa, then there will also be a Halachah l'Moshe mi'Sinai (or Sevara) saying that one *may* make an Eruv for such a Techum to permit walking another 12 Mil. We see that there is even such a thing as *Eruvei* Techumin mid'Oraisa.

Perhaps for this reason, the RA'AVAD (cited by the Rashba and Ritva) explains that the Gemara does not mean that there is no such thing as Techumin d'Oraisa. The Gemara means that the reason the Rabanan prohibited walking 2000 Amos has nothing to do with the law of 12-Mil Techumin d'Oraisa (because if their enactment was related to the Isur d'Oraisa, why did they choose to prohibit walking such a small fraction of the Torah's shiur, i.e. but 2000 Amos?). Rather, the Rabanan derived an inference from the cities of the Levites (Eruvin 51a) that the boundaries of a city extend 2000 Amos beyond its walls, and therefore they enacted a Gezeirah that one may walk up to 2000 Amos from his place of Shevisah on Shabbos and Yom Tov.

(c) The RITVA says that the Gemara means that *Rebbi Yosi's* opinion is that there is no Techumin d'Oraisa at all, not even 12-Mil Techumim. Other Tana'im, however, hold that there is a law of 12-Mil Techumin d'Oraisa.


QUESTION: The Gemara says that according to Ayo, one may only make an Eruv stipulating that if the Chacham comes to one side or the other side of the town, the Eruv will be to that side. If one stipulates that if two Chachamim come to each side of the town then he reserves the right to choose the side on which his Eruv will take effect, the Eruv does not work.

In either case, asks the Gemara, one is utilizing Bereirah! Why, then, is the second case not valid and the first case valid? location).

Why didn't the Gemara suggest a very simple difference between the cases of Ayo. Perhaps even if one stipulates "if the Chacham comes from the East my Eruv is to the East," the Eruv is valid, since it involves no more than a normal case of stipulating a "Tenai" (condition). It is comparable to saying, "If you so such and such, this Get will be a valid Get." However, when the person says "If two Chachamim come, I will choose tomorrow where I want my Eruv to be retroactively," Bereirah is involved rather than a simple yes/no choice. Therefore the Eruv is not valid!


(a) A Tenai works only because it is in the hands of one of the parties involved to fulfill the condition, and it was his intention that the condition be fulfilled at the time that he stipulated the Tenai. (That is, because he plans on fulfilling it and wants the deal to go through, the event contingent upon the condition takes effect *immediately*, even before the Tenai has been fulfilled. If the Tenai ends up not being fulfilled, then the event that was contingent upon it is uprooted retroactively. It is possible uproot an event retroactively, but not to cause it to take effect retroactively.)

That is not the case in Ayo's case. In the case of making an Eruv, the condition (that the Chacham comes from this side) is not in the hands of the person who made the statement to fulfill. It is dependent on the Chacham, who himself has nothing to do with making the Eruv. Since the Eruv does not depend on something which is in your hands to fulfill, it is considered a case of Bereirah. (RASHI, Gitin 25b)

(b) The RAMBAN in Gitin (25b) argues with Rashi and explains that a Tenai is when there are two possibilities -- either the event will occur or it will not occur. On the other hand, when trying to make something happen which can occur in one of several ways, then it is not a Tenai but a question of Bereirah. The case of the Eruv dependent on the Chacham coming to one of two sides is such a case and therefore it involves Bereirah. The event -- the Eruv taking effect -- is going to happen in one of two places; the arrival of the Chacham will determine where the Eruv takes effect.

Still, why is the case of the Chacham a case of Bereirah? We can view it as two completely separate conditions: (1) If the Chacham comes to the east, then the Eruv will be to the east, and if he does not come to the east, then there will be no Eruv to the east. (2) If the Chacham comes to the west, then the Eruv will be to the west, and if he does not come to the west, then the Eruv will not be to the west. (REBBI AKIVA EIGER in a Ma'arachah on Eruvin.) TOSFOS, end of Yoma 56a, in fact asks this question on the explanation of the Ramban.

Apparently, the Ramban maintains that the two Eruvei Techumim cannot be viewed as two independent events. Rather, one event is taking place (making an Eruv), and there are two possibilities as to how it will take place (to the east or west). The reason for this is that one cannot make two Eruvs to be Koneh Shevisah in two places (since a person lives only in one place at a time.) Therefore, when the person adds that if the Chacham comes to the other side his Eruv will be to that side, it is viewed as an addendum to his first condition.

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