he sendeth down water from the sky so that valleys flow according to their measure and the flood beareth swelling foam from that which they smelt in the fire in order to make ornaments and tools riseth a foam like unto it thus allah coineth the true and the false. then as for the foam it passeth away as scum upon the banks while as for that which is of use to mankind it remaineth in the earth. thus allah coineth the similitudes.
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