لَوْ نَشَاءُ جَعَلْنَاهُ أُجَاجًا فَلَوْلَا تَشْكُرُونَ (70)
(56:70) If We had so pleased, We could have made it bitter. *30 So why would you not give thanks? *31
*30) In this sentence an important manifestation of Allah's power and wisdom has been pointed out. Among the wonderful properties that Allah has created in water one property also is that no matter what different substances are dissolved in water, when it changes into vapour under the effect of heat, it leaves behind aII adulterations and evaporates only with its original and actual component elements. Had it not possessed this property the dissolved substances also would have evaporated along with the water vapours. In this case the vapours that arise from the oceans would have contained the sea salt, which would have made the soil saline and uncultivable wherever it rained. Then, neither could man have survived by drinking that water, nor could it help grow any vegetation. Now, can a man possessed of any common sense claim that this wise property in water has come about by itself under some blind and deaf law of nature? This characteristic by virtue of which sweet, pure water is distilled from saltish seas and falls as rain, and then serves as a source of water-supply and irrigation in the form of rivers, canals, springs and wells, provides a clear proof of the fact that the Providence has endowed water with this property thoughtfully and deliberately for the purpose that it may become a means of sustenance for His creatures. The creatures that could be sustained by salt water were created by Him in the sea and there they flourish and multiply. But the creatures that He created on the land and in the air, stood in need of sweet water for their sustenance and before making arrangement of the rainfall for its supply He created this property in water that at evaporation it should rise clear and free of everything dissolved in it.
*31) In other words, "Why do you commit this ingratitude in that some of you regard the rainfall as a favour of the gods, and some others think that the rising of the clouds from the sea and their raining as water is a natural cycle that is working by itself, and still others, while acknowledging it as a mercy and blessing of God, do not admit that God has any such right on them that they should bow to Him alone? How is it that while you derive so much benefit from this great blessing of Allah, in return you commit sins of disbelief and polytheism and disobedience of Him?"