Siman - Eruvin Daf 31
- Placing an eruv on a grave
In the Mishnah on Daf 26b, Rebbe Yehudah said that a kohen may place his eruv, אפילו בין הקברות - even in a cemetery, מפני שיכול לחוץ ולילך ולאכול – because the Kohen can make a partition between himself and the grave and then go (through the cemetery) and eat his eruv.
After determining on our Daf how exactly the Kohen can access the eruv without becoming tamei, the Gemara seeks to understand why the Rabbanon forbid using it. The Gemara explains that, קסברי אסור לקנות בית באיסורי הנאה – they hold that it is prohibited to acquire a dwelling place with objects forbidden from benefit, and therefore he may not place his eruv on a grave. Rashi explains that a grave and the implements of a corpse are forbidden for one’s personal benefit, based on a gezeirah shavah, which connects the passing of Miriam with the subject of the eglah aruphah. Just as one cannot derive benefit from the decapitated calf, so too one cannot derive benefit from a corpse or its implements.
- Using maaser rishon whose terumos maasros had been taken for an eruv
The next Mishnah states that one may make an eruv with מעשר ראשון שנטלה תרומתו, - maaser rishon whose terumah had been taken. The Gemara clarifies that the Mishnah is coming to teach that maaser rishon is permissible to use שהקדימו בשבלין – when the separation was done while the grain was still in the ears, before the owner was even obligated to separate terumah for the Kohen. The owner therefore only needs to separate maaser rishon and terumas maasros, but not terumah gedolah.
The Gemara points out the Mishnah’s teaching is in accordance with Rebbe Abahu who said in the name of Reish Lakish that מעשר ראשון שהקדימו בשבלין פטור מתרומה גדולה – maaser rishon which was taken off while the grain was still in the ears, is patur from terumah gedolah as it says in the passuk regarding maaser rishon, והרמתם ממנו תרומת ה' מעשר מן המעשר – And you shall offer up from it Hashem’s terumah, a tithe of the maaser. מעשר מן המעשר אמרתי לך – I told you, (referring to the Levi), to give the Kohen a tithe of the maaser, ולא תרומה גדולה מן המעשר – and not both terumah gedolah and terumos maaser from the Levi’s maaser rishon.
- A child cannot be a shaliach to place an eruv
The next Mishnah states that if one sends his eruv in the hands of a katan, it is not a valid eruv, even if he deposits it in the proper place. The Gemara asks why a katan cannot serve as a shaliach, since Rav Huna said, קטן גובה את הערוב – a child may collect the eruv food from members of the chatzeir for an eruv chatzeiros. The Gemara answers that our Mishnah is dealing with an eruv techumim, whereas Rav Huna was discussing an eruv chatzeiros. Rashi explains that the purpose of an eruv techumim is to acquire a Shabbos residence, and a minor lacks the power of acquisition, and therefore he cannot serve as a shaliach. In the case of the eruv chatzeiros, however, the child is merely gathering the eruv food into one place, and automatically the various dwellings merge into one place.
