A temporary dwelling
Reprinted from The Jewish Religion: A Companion, Oxford University Press. © Louis Jacobs, 1995.
A sukkah is a booth in which Jews are commanded to dwell during the festival of Tabernacles [Sukkot], as stated in the book of Leviticus (23:42‑5): "You shall live in booths [sukkot] seven days; all citizens in Israel shall live in booths, in order that future generations may know that I made the Israelite people live in booths when I brought them out of the land of Egypt, I am the Lord your God."
According to the talmudic rabbis, a sukkah has to have at least three walls (though the third need not be a complete wall) and a covering. It has to be at least 4 square cubits in size, but this does not necessarily mean that it has to have a square or oblong shape A circular sukkah, for instance, is valid provided it covers an area of at least 4 square cubits (a cubit is approximately 18 inches). The covering must be of things that grow from the soil (e.g. straw or leaves of trees), but it must be detached from the soil, so that it is not valid to use the leaves of a tree still growing from the soil as a sukkah covering. The covering has to have more shade than light; that is, there must be more covered than uncovered space. The covering can be quite thick, although it is customary to make the covering sufficiently sparse for the stars to be seen through it. The sukkah has to be outdoors. A sukkah under a roof is not a valid sukkah, nor is it valid to have a sukkah underneath, say, the overhang of a balcony.
All full meals should be eaten in the sukkah, that is, meals at which bread is partaken of, although some pious Jews do not eat or drink anything outside the sukkah. In Talmudic times people slept in the sukkah, treating it as their abode for the duration of the festival. In Western lands the majority of Jews do not sleep in the sukkah (some of the more pious still do, however). The rationale for this is that where to stay in the sukkah is uncomfortable, the obligation is set aside and in colder climates it is certainly uncomfortable in autumn to sleep outside in the sukkah. For the same reason there is no obligation to eat in the sukkah when it is raining and the rain comes through the covering.
One example of a sukkah.
According to the authorities, it is undesirable for a man to stay in the sukkah even when the rain comes in, on the grounds that to persist in carrying out a religious precept when the law does not demand it suggests an attitude of religious superiority, of trying to be more pious than the Torah demands. Nevertheless, it is the custom of the majority of Hasidim to stay in the sukkah even when it is raining. The Hasidic rationale is that the reason there is no obligation to stay in the sukkah when it rains is because of discomfort and a true Hasid will never find discomfort in staying in the sukkah, no matter how severe the weather. Nowadays, many sukkahs are built with a roof on pulleys so that, after the meal, the roof can be lowered so as to prevent rain coming into the sukkah during the times it is not used. When the time comes to use the sukkah the roof is raised and the sukkah is once again open to the sky. The raising and lowering of the roof does not constitute forbidden 'work' and can) therefore, be done on the Sabbath and the festival days, Synagogues often have an adjacent sukkah to which the congregation repairs for Kiddush after the service.