He sends down from the sky water and flows the valleys according to their measure, and carries the torrent a foam rising. And from what they heat [on] it in the fire in order to make ornaments or utensils, a foam like it. Thus sets forth Allah the truth and the falsehood. Then as for the foam it passes away (as) scum, and as for what benefits the mankind, remains in the earth. Thus sets forth Allah the examples.