A succah which has three walls is kosher. Of these three walls, two must be complete (a full amount of at least seven tefochim width), and the third may be as little as one tefach wide. (Gemara Succah 2a) The Medrash relates that Iyov complained about the suffering which he had to endure. When Hashem showed him the three walls of the succah, with two being complete and the third being of one tefach, Iyov was placated. -- Midrash Pli’ah
The Aruch LaNer provides an explanation of this Medrash which associates a succah with Iyov and his travails. There is a classic difference of opinion which appears periodically in the Gemara regarding the construction of the succah. One opinion holds that a succah be a form of a permanent building. This view requires that a succah be built from four complete walls. The other view is that the basic principle of the mitzvah of succah is for us to go out from our permanent houses and to reside in temporary dwellings. From this perspective, we understand that a succah may be made from two complete walls, and the third wall can be scaled back and be the width of a tefach. This type of structure symbolizes how man should realize that his sojourn in this world is only temporary, and his ultimate residence will be the domain of the souls in the World-to Come.
As Iyov suffered his pains, he was troubled that his existence in this world was being disturbed with physical agony. From his perspective, this world was the main place in which man exists, and this very experience was unpleasant. Hashem alerted Iyov that this world was merely transient, and the World-to-Come was the eternal goal where that which is truly good is to be found. By showing Iyov the halachah that a succah can have only three walls, of which the third may be only a tefach, Hashem demonstrated that this world’s existence is temporary, as it merely serves as a portal of passage to the eternal world of the souls in the World-to-Come. If a person’s lot is one of suffering, he need not feel that he has been deprived of his deserved comfort and tranquility. In fact, this state of difficulty should provide hope that his true reward will be eternal. (Rabbi Ben-Zion Rand)
