Midrash sa Isaias 5:25: Sifra

1) (Vayikra 26:4) ("Then I shall give your rains in their proper times, and the earth shall yield its produce, and the tree of the field shall yield its fruit.") "Then I shall give your rains in their proper times": in the nights. But perhaps (the meaning is) on the eves of Sabbath (This cannot be, for) they said: Even if the years were like those of Eliyahu and the rains descended on the eves of Sabbath, it is nothing but a sign of cursing. How, then, am I to understand "Then I shall give your rains in their proper times"? In the nights. It happened in the days of Herod that the rains descended in the nights. In the morning the sun shone and the wind blew and the earth dried, and the workers went out to their work, knowing that their deeds were for the sake of Heaven. "Then I shall give your rains in their proper times": on Wednesday nights and on Sabbath nights. It happened in the days of Shimon b. Shetach and in the days of Queen Shlamtzah that the rains descended from the nights of Sabbath to the nights of Sabbath until the wheat became like kidneys, and the barley like olive-stones, and the lentils like golden dinars. And the sages tied up some of them and left them for future generations to apprise them (by contrast) what were the fruits of sin. As it is written (Jeremiah 59:2) "Your transgressions have diverted these (blessings)", (Isaiah 5:25) "And your sins have hidden (His) face from you against hearing", (Jeremiah, Ibid.) "They (your sins) have withheld the good from you."