he sends down water from the skies and the channels flow each according to its measure but the torrent bears away to foam that mounts up to the surface. even so from that which they heat in the fire to make ornaments or utensils therewith there is a scum likewise. thus doth allah show forth truth and vanity. for the scum disappears like forth cast out while that which is for the good of mankind remains on the earth. thus doth allah set forth parables.
أنزل من السماء ماء فسالت أودية بقدرها فاحتمل السيل زبدا رابيا ومما يوقدون عليه في النار ابتغاء حلية أو متاع زبد مثله كذلك يضرب الله الحق والباطل فأما الزبد فيذهب جفاء وأما ما ينفع الناس فيمكث في الأرض كذلك يضرب الله الأمثال