Daf Yomi - Sukkah 19 - Highlights

The Mishna on daf 17 ruled that if the s'chach is distanced from the walls three tefachim or more, the sukkah is disqualified. If there is ineligible s'chach , the sukkah is valid, providing that it not more than four amos away from the walls. Abaye, who maintains that a wall can be created by applying the principle of "the tip of the roof extends down and we close" is forced to explain this Mishna that it is referring to a case where he made the s'chach level with the roof of the porch. This prevents the edge of the roof to be seen and therefore it cannot be extended downward.

In Pumpadisa they learned the argument between Abaye and Rava differently. They argued in a case where there were pillars in the front of the porch and they were spaced within three tefachim of each other. The debate is based on the question if lavud can be applied in a case where these pillars were intended for the porch and not for the sukkah.

In this version it was agreed upon that without pillars, the sukkah is disqualified, yet Rav Ashi chanced upon Rav Kahana sitting in such a sukkah. Rav Kahana explained to him that his sukkah had a wall because there was a pillar that was flush on one side yet visible on the other side and that is deemed as a wall.

A Braisa is cited that states that s'chach which protrudes from a sukkah is also regarded as a sukkah. There are several different explanations as to what the case is referring to. Ula learns that the s'chach and the walls extend outward from the back of the sukkah forming another sukkah and that is valid even though the center wall was intended for the other side. Rabbah and Rav Yosef learn that it is referring to where one of the outside walls extends further than the other one and the entire sukkah is deemed valid. Rav Yochanan understands it to mean that a minor part of the sukkah has more sunlight than shade, yet we are not concerned and even that part is valid. Rabbi Yoshia learns that it is referring to a case where there is less than three tefachim of ineligible s'chach.

The Gemora makes a distinction between ineligible s'chach less than three tefachim and open space less than three tefachim. The Gemora states that they both combine to complete the minimum measurement of a sukkah, however one you can sleep under and fulfill your obligation and one you cannot. Rashi learns that one can sleep under the ineligible s'chach but he can't sleep under the open space.

The Mishna cites an argument if one leans a wall against another one if the sukkah is valid. One Tanna maintains that it is disqualified because there is no roof. The Gemora cites cases where he would agree that it is valid.

There is a debate in the Mishna if one can use mats for s'chach. Some mats are susceptible to becoming tamei and thereby unfit to be used as s'chach. There is a discussion at length as to the distinctions between a large one which is usually intended for covering a sukkah and a small one which is intended for sleeping purposes. The Gemora discusses what the halacha would be if there was no specific intention.