Also in the fifteenth day of the seventh month, when ye have gathered in the fruit of the land, ye shall keep a feast unto the Lord seven days: on the first day shall be a sabbath, and on the eighth day shall be a sabbath. Ye shall dwell in booths seven days; all that are Israelites born shall dwell in booths: That your generations may know that I made the children of Israel to dwell in booths, when I brought them out of the land of Egypt: I am the Lord your God. (Le 23:39, 42-3)
When God appointed a feast for the Jews to follow the harvest, He decreed that they should dwell for seven days in booths during that feast. This was to show new generations that He had made Israel dwell in tents after bringing them out of Egypt.
Several questions could be raised. Why remind people of the obvious, that they dwelt in tents as they travelled from Egypt to Canaan? Why does this reminder not come during Pesach, the celebration of the exodus? The farmers have toiled in the heat to harvest their crops; why live in booths now when it is cooler rather than then, when it might have been more comfortable? What does living in tents have to do with bringing the first fruit of the harvest?
There is a deeper meaning to living in the tents that just reminding Israel that the expected living arrangements would be tents. That deeper meaning is also related to the harvest, more than to the miracles of the beginning of the exodus. The timing of the requirement to live in succos (booths) is important.
Historians have told us that the movement from man as a "hunter-gatherer" toward "civilization" was keyed by the development of agriculture. That is, until man learned to plant crops he had no opportunity to form cities and no time to develop the arts and technology. What man has become is largely a result of his learning to manipulate his environment. He can settle in one place, rather than follow the game, and he can form large groups tied to a particular land, such as towns, cities, even nations.
What better time for God to remind us of our temporary nature than when we are celbrating our permanence? Now that you have land to grow crops, now that you have the land for a national inheritance, you must remember that it was not always so. God made you dwell in tents before He gave you the land. Your ancestors knew they were travelling toward a goal, not having attained it. After the days of repentance, when one brings the first fruits of his crops, he is tempted to say "I have it made. My sins are atoned for, my work has produced all this bounty. I have attained the goal."
Instead, God reminds us that Israel lived in tents. They stopped for long periods on their journeys, but they lived in tents. By tying the Feast of Tabernacles to the bringing of the first fruits, God is saying, "You have it good, but you aren't there yet. I have a better place waiting for you. Remember, though you build houses you are still living in the tents you know as your bodies. Stay on the path to the real Promised Land."
(The first day of Succoth this year is October 14.)