Midrash sobre Levítico 26:4

1) (Vayikra 26:3) ("If in My statutes you walk, and My mitzvoth you keep to do them,") "If in My statutes you walk … (Vayikra 26:4) then I shall give your rains in their proper times, etc.": We are hereby taught that the Holy One Blessed be He yearns that Israel toil in Torah. And thus is it written (Tehillim 81:14-15) "Would that My people heeded Me, that Israel walked in My ways! In an instant I would humble their foes and against their oppressors turn My hand!" (Isaiah 18:19) "Would that you heeded My mitzvoth — then your peace would be like a river and your righteousness like the waves of the sea. And your seed would be like the sand and the issue of your loins like its innards. Its name would not be cut off and blotted out before Me!" And (Devarim 5:26) "Who would grant that this their heart would be in them to fear Me and to keep all My mitzvoth all the days, so that it be good for them and for their children forever" — whence we learn that the Holy One Blessed be He yearns that they toil in Torah.

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."

2) "Then I shall give your rains in their proper times": (but) not the rains of all the lands. How, then, am I to understand (Bereshith 28:14) "And all the families of the earth will bless themselves in you and in your seed"? That there will be plenty in Eretz Yisrael and famine in all the lands. And they will come and buy from you and enrich you with money, as it is written (Bereshith 47:14) "And Yosef gathered in all the money that was found in the land of Egypt and in the land of Canaan for the food that they bought." And (Devarim 33:25) "As your days, your flow" — All of the lands will "flow" money and bring it to Eretz Yisrael.