With it He produces for you corn, olives, date-palms, grapes and every kind of fruit: verily in this is a sign for those who give thought. An-Nahl 16:11 ⧉
Tafsir:
The clouds send down rain from the sky and, thanks to this, extremely fruitful results appear on the earth down below. This coordinated and harmonious action of ‘heaven and earth’ clearly proves that the God of earth is the same as that of heaven. There is perfect harmony among the different parts of the universe. This harmony is definite proof of the fact that the Creator and Lord of the whole universe is only one. In the present structure of the universe, there is no scope for more than one God, and when the real Creator and Lord is one God, making any thing other than Him an object of worship will be absolutely indefensible.