فَإِن لَّمْ يُصِبْهَا وَابِلٌ فَطَلٌّ
(And if it does not receive Wabil, a Tall suffices it.) Ad-Dahhak said that the `Tall' is light rain. The Ayah indicates that the garden on the Rabwah is always fertile, for if heavy rain does not fall on it, light rain will suffice for it. Such is the case regarding the believer's good deeds, for they never become barren. Rather, Allah accepts the believer's righteous deeds and increases them, each according to his deeds. This is why Allah said next,