One of the blessings promised to the Jewish people as a reward for following the Torah is: “I will provide your rains in their season.” The Sages explain that this means rain will fall at a time when it will not interrupt life’s routine, while at the same time it will water the crops.

When the verse states: “I will provide your rains in their season” (Leviticus 26:4), this means that it will rain at night. In the days of King Herod, rain would fall at night, and in the morning the sun shone and the wind blew, the clouds scattered and the land dried. The workers went out and engaged in their labor and knew that their actions accorded with the will of their Father in Heaven [since it rained in a manner that did not impede their routines]. Alternatively, when the verse states: “I will provide your rains in their season” (26:4), this means that it will rain on the night of Shabbat [i.e., Friday night, a time when people are inside their homes]. There was an incident in the days of Shimon ben Shatah and Queen Shlomtzion when rain would fall every Shabbat night, to the extent that wheat kernels grew to the size of kidneys, barley kernels grew to the size of olive pits, and lentils grew to the size of gold dinars. The Sages collected them and stored them for future generations to see. Why did the Sages go to such effort? To inform [the Jewish people in the future who will not observe the commandments] to what degree the sin has an effect, in fulfillment of what is stated: “Your iniquities have diverted these, and your sins have withheld good from you” (Jeremiah 5:25). (Vayikra Rabba 35)