(Qaaf) 50 : 9
وَنَزَّلْنَا مِنَ السَّمَاءِ مَاءً مُبَارَكًا فَأَنْبَتْنَا بِهِ جَنَّاتٍ وَحَبَّ الْحَصِيدِ
And We sent down from the sky the blessed water, thus We caused to bring forth with it gardens and the harvesting grains.
Even though the vapour risen from the seas and from other water reservoirs due to evaporation causes for rainfall, rain water doesn’t contain salt or any impurities. So it is suitable for drinking and watering the plants. That is why it is mentioned in this verse about the rain fall as ‘the Blessed water’. Today the rain water directly collected at the time of rainfall is used in Batteries. See explanation 10: 24; 18: 45; and 39: 21.