Siman - Succah Daf 18
- אויר שלשה בסוכה גדולה ובסוכה קטנה
Abaye said: אויר שלשה בסוכה גדולה – If there is open space of three tefachim in the s’chach of a large succah, ומיעטו בין בקנים בין בשפודים – and he reduced it, either with sticks (which are valid as s’chach) or with spits (which are passul)הוי מיעוט - it is an effective reduction, meaning the gap now lacks the width of three tefachim necessary to passul the succah. בסוכה קטנה – However. in a small succah, which is only seven by seven tefachim, if he reduced it with sticks it is effective, but if he reduced it with spits it is not effective. Rashi explains that sticks are effective in reducing the gap via lavud. The spits are not effective since the open space and spits together form a gap in the s’chach of three tefachim, they are significant enough to be regarded as separate from the s’chach, and the valid s’chach lacks the requisite dimensions of seven-by-seven tefachim.
- לבוד מן הצד ומן האמצע
The Gemara qualifies that a gap of less than three tefachim wide does not passul a succah מן הצד – if the gap is at the side, between the s’chach and a wall. But with regard to a gap in the middle of the succah, Rav Acha and Ravina disagree. One says יש לבוד באמצע – the principle of lavud applies even in the middle, and one says, אין לבוד באמצע – lavud does not apply in the middle. The one who holds יש לבוד באמצע learns it from a case taught in a Baraisa regarding a mavoi where two korahs project from opposite walls but do not touch each other, leaving a gap in the middle. If the gap is less than three tefachim, it is not necessary to bring another korah, due to lavud. The other opinion, who holds that lavud only applies at the side, would answer שאני קורות דרבנן – the law of korahs is different since it is only a d’Rabbanon.
The one who holds אין לבוד באמצע, learns it from a Mishnah in Ohalos, where a source of tumah is opposite an ארובה – a skylight that does not have an opening of a tefach, and the din is כל הבית כולו טהור – the whole house is tahor. This Mishnah treats the skylight as an open gap in the roof, even though it is less than three tefachim wide. The other opinion who holds יש לבוד באמצע, would answer, שאני הלכות טומאה דהכי גמירי להו – the laws of tumah are different, for this is how they were taught at Sinai. It is a Halachah LeMoshe MiSinai regarding tumah, that lavud only applies to walls. This law cannot be automatically extended to other halachos, such as succah.
- פי תקרה יורד וסותם מחלוקת אם אמרינן
It was stated:כשרה סיכך על גבי אכסדרה שיש לה פצימין – If one placed s’chach on a porch that has columns in front of it, positioned at intervals of less than three tefachim, the succah is kosher. שאין לה פצימין – If it does not have such columns, Abaye says that it is kosher and Rava says that it is passul. Abaye says the succah is kosher אמרינן פי תקרה יורד וסותם – because we say that “the edge of the roof extends downward and seals,” meaning the edge of each porch roof is viewed as extending downward to form the succah’s requisite partitions. Rava says that the succah is passul לא אמרינן פי תקרה יורד וסותם. Rava challenged Abaye and said that according to Abaye, אפילו הפחית דופן אמצעי – even if the middle wall of a three walled succah collapsed, the succah should still be kosher, because the edge of the s’chach is יורד וסותם – descends and seals to replace the collapsed wall. Abaye said that he concedes that the succah is passul in that case, דהוה ליה כמבוי מפולש – because it is like an open alleyway.
