The Joy of the Succah
The succah is a very great joy: to such a degree that it cannot be permanent, but a temporary dwelling. But it stands in one place, because waves of light expressing that joy pour forth. One wave rises and with no interruption descends, and a second, new wave flows, one which is brighter and more joyful. It appears as if it is all one succah. But in truth, at every moment and fraction of a moment, there is literally a new succah. And since the joy is new and the newness is constant, this is "the time of our joy."
Arpelei Torah, quoted in Moadei Harayah, p. 95