Sukkah

A sukkah is defined by its covering. The walls may be almost anything, canvas, board, an existing wall of a house, a hedge, and there are detailed rules about how many are needed and how complete they must be, but the sechach on top is where the halakhic weight sits. It must be material that grew from the ground and has been cut, so branches, reeds, bamboo or unprocessed boards qualify while a fitted roof does not. It must not be a manufactured vessel, and it must not be attached in a way that makes it a permanent structure. It must be thick enough that the shade inside exceeds the sunlight, and thin enough that the larger stars can be seen through it and rain comes through.

Joseph Karo's Shulchan Aruch works through these conditions in detail, along with the question of what invalidates a sukkah built under a tree or a balcony. The effect of the rules taken together is a structure that is unmistakably a shelter and unmistakably inadequate as one, and that is the intended result rather than a compromise between competing requirements. A roof that keeps out the rain would be a better roof and a worse sukkah. The rules about the stars and the rain are what stop the booth from quietly becoming a garden room, which is the direction convenience would take it in every generation.

The commandment in Leviticus is to dwell in booths for seven days so that later generations will know that the people were made to dwell in booths when they were brought out of Egypt. The rabbinic tradition took dwelling seriously: the obligation is to live in the sukkah, treating it as the home for the week, so meals are eaten there and, where climate and local custom allow, people sleep there. It is not a place of worship in the sense a synagogue is. It holds no ark, no scrolls and no fixed liturgy of its own, and there is nothing in it that could not be in a house. What it has is impermanence, and the impermanence is the content. A household that has spent the year making its home secure is required to move out of it into something that will not survive a strong wind, and to do so immediately after the most solemn days of the year. Children commonly decorate the walls, guests are invited, and the whole structure comes down at the end of the week.

The Encyclopaedia Judaica records the range of local customs attached to it, which vary considerably between communities while the requirements for the roof do not. In colder climates the obligation to sleep in it is commonly waived on the principle that a commandment to dwell does not extend to conditions in which nobody would dwell, and that ruling is itself a good illustration of how the tradition handles a requirement that the weather makes impossible.