Ar-Ra'd 13:17 انزل من السماء ماء فسالت اودية بقدرها فاحتمل السيل زبدا رابيا ومما يوقدون عليه في النار ابتغاء حلية او متاع زبد مثله كذالك يضرب الله الحق والباطل فاما الزبد فيذهب جفاء واما ما ينفع الناس فيمكث في الارض كذالك يضرب الله الامثال ١٧

He sends down from the sky, rain, and valleys flow according to their capacity, and the torrent carries a rising foam. And from that [ore] which they heat in the fire, desiring adornments and utensils, is a foam like it. Thus Allāh presents [the example of] truth and falsehood. As for the foam, it vanishes, [being] cast off; but as for that which benefits the people, it remains on the earth. Thus does Allāh present examples.