If we compare the way in which the festivals in the month of Tishrei are treated by the Torah and by Chazal, we arrive at an interesting observation: the impression one gets from the Torah's description is of days of joy and happiness, in apparent contrast to the dimension of justice so strongly emphasized by Chazal. Through an analysis of the holiday of Sukkot, we can understand the central motif of the prayers for rain, which occupies an important position in the Sukkot ritual. 

Courtesy of the Virtual Beit Midrash, Yeshivat Har Etzion