Siman - Eruvin Daf 34
- A makom shevisa on top of a closet
On Daf 33b, Rebbe Yirmiyah said that the eruv in a basket is valid even if it is above ten tefachim high in a tree which is four tefachim wide, since the basket can be tilted downward bringing the eruv within ten tefachim of the ground, which has the din of a karmelis, and thereby making it accessible to bring it into a reshus harabim during bein hashemashos. The Gemara challenges Rebbe Yirmiyah based on a Baraisa that states that if one intended to establish his makom shevisa (Shabbos residence) on top of a closet which was placed against a wall, and he placed the eruv in the closet below ten tefachim, (which Rashi explains means at a height of nine tefachim in a place people use to adjust their loads which has the status of reshus harabim), the eruv is invalid. The eruv is in a reshus harabim and it requires to be transferred to the top of the closet, which is a reshus hayachid. The Gemara asks why the eruv is not valid being that one may tilt the closest, as Rebbe Yirmiyah stated.
Rebbe Yirmiyah answered that the closet mentioned in the Baraisa was nailed to the wall, making it impossible to tilt the closet. Rava answered that even if the closet was not nailed into the wall, the eruv would be still be invalid since the Baraisa was discussing a tall closet, that if one would tip the top forward, it would extend more than four amos from the wall, and then he would not be within four amos of the place that he had designated as his makom shevisa.
- An eruv in a pit one hundred amos deep
The Mishnah on Daf 32b stated that if one placed an eruv in a pit, even if it was a hundred amos deep, the eruv is valid. The Gemara seeks to determine where this pit was located. If it was in a reshus hayachid, then why does the Mishnah state that “even if the pit is a hundred amos deep,” just as a reshus hayachid extends all the way to the heavens, so too does it extend all the way downwards, and therefore there is no chiddush in saying that “even if the pit is a hundred amos deep”. On the other hand, if the pit is in a reshus harabim, then it is obvious that the eruv is invalid since the person’s makom shevisa is in a reshus harabim and the eruv is in a reshus hayachid. The Gemara concludes that the pit is in a karmelis, and the Mishnah is according to Rebbe who holds that, כל דבר שהוא משום שבות לא גזרו עליו בין השמשות – any Shabbos prohibition which is a d’Rabbonon is not forbidden during bein hashemashos.
- An eruv in a closet with a lost key
The next Mishnah states, נתנו במגדל ואבד המפתח – If he placed the eruv in a closet, and then he locked it, and then he lost the key, making the eruv inaccessible, according to the Tanna Kamma the eruv is still valid. Rebbe Eliezer said that if he does not know where the key is, it is not a valid eruv.
The Gemara asks why the eruv should be valid according to the Tanna Kamma, since his makom shevisa is in one place and the eruv is in another. Rashi explains that even though they are both in a reshus hayachid, the eruv is still inaccessible making it as if they are in two different places. Rav and Shmuel both say that the case is dealing with a closet made of bricks, and is going according to Rebbe Meir who holds, פוחת לכתחילה ונוטל, that if a house of produce was sealed, making them inaccessible on Yom Tov, one may break through the wall and take the fruit. The Gemara clarifies that the bricks of the house were not cemented together, so breaking the wall would not be violating soser - demolishing.
