A joyful period is ushered in by the festival of Sukkot that compensates for the solemn period of the yomim noraim. Sukkot is "the season of our rejoicing.,, On Sukkot we have a mitzvah that is truly unique, for the Sukkah is the only mitzvah that literally encompasses us, as we walk into it.
The sukkah reminds us of the "Clouds of Glory" that surrounded our people during their wandering through the desert on the way to the Promised Land. Everybody then saw the special Divine protection that G-d bestowed upon them during those difficult years.
But although the "Clouds of Glory" disappeared in the fortieth year, on the eve of their entry into the Land of Israel, we have never ceased to believe that G-d gives us His own protection, and that is why we have outlived our greatest enemies in all generations.
We know of course that we enjoy this Divine protection only as long as we remain loyal Jews, faithful to our G-d and our Torah. This explains why we have Simchat Torah (rejoicing with our Torah) at the end of the Sukkot festival… But more about this day later!