Siman - Eruvin Daf 102
- How to create shade for rams on Shabbos
The Gemara brings several teachings of the d’Rabbanon issur of building a temporary ohel. הנהו דכרי דהוו ליה לרב הונא – Rav Huna had some rams that required shade from the sun in the daytime and required fresh air at night. During the week, mats were spread over their pen by day to provide shade and were removed at night to provide ventilation. Rav Huna came before Rav and asked him how he should give the rams shade on Shabbos day without creating an ohel. Rav answered that when he wants to expose the pen before dusk erev Shabbos, זיל כרוך בודייא ושייר בה טפח – go and roll up the mat but leave one tefach spread out, למחר פשטה – then the following day, on Shabbos, unroll it. He explained that since the mat was already spread out a tefach before Shabbos, one who unrolls the rest of it on Shabbos, מוסיף על אהל עראי הוא ושפיר דמי – is only adding to an already existing temporary structure, and that is permitted.
- Reinserting pivots
The second Mishnah on the Daf states according to the Tanna Kamma, מחזירין ציר התחתון במקדש אבל לא במדינה – One may reinsert a bottom pivot in the Beis Hamikdash but not in the provinces, and the top pivot may not be reinserted neither in the provinces nor in the Beis Hamikdash. The Gemara clarifies that replacing the lower pivot is an issur d’Rabbanon out of concern that one will hammer it in. There is a rule that אין שבות במקדש - The Rabbanon suspended their decrees when they interfere with the avodah in the Beis Hamikdash. Replacing the upper pivot, however, which makes the door functional, is an issur d’Oraysa since the Tanna Kamma holds, יש בנין בכלים – Building with keilim is the melocho of boneh, therefore, it is assur even in the Beis Hamikdash.
Rebbe Yehuda says that even the top pivot may be reinserted in the Beis Hamidkash since he holds that אין בנין בכלים it is only an issur d’Rabbanon, and therefore it is permitted in the Beis Hamikdash, and he holds that the lower pivot is mutar even outside the Beis Hamikdosh.
- A Kohen replacing a bandage with dressing after doing the avodah
The next Mishnah deals with a Kohen with a wound who deliberately removed a bandage with the dressing to perform the avodah so that it would not constitute a chatzitzah, and now he wishes to replace it. מחזירין רטיה במקדש – One may replace a dressing in the Beis Hamikdosh for the sake of avodah, but not in the provinces as that would be an issur d’Rabbanon. Rashi explains that the Rabbanon were concerned that one may commit the melachah of smoothing out the dressing. Even though replacing the dressing is normally forbidden even in the Beis Hamikdosh, the Rabbanon granted a special dispensation. They were concerned that if the Kohen would not be allowed to replace the dressing after doing the avodah, he would choose to keep the bandage on and refrain from doing the avodah.
