۞ And make mention (O Muhammad) of the brother of A'ad when he warned his folk among the wind-curved sandhills - and verily warners came and went before and after him - saying: Serve none but Allah. Lo! I fear for you the doom of a tremendous Day. 21 They said, "Have you come to turn us away from our gods? Show us that with which you threaten us if you are truthful". 22 He said, 'Knowledge is only with God, and I deliver to you the Message with which I was sent; but I see you are an ignorant people.' 23 So when they saw it as a cloud advancing towards their valleys, they said: "This is just a passing cloud that will bring us rain." "No. It is what you were trying to hasten: The wind which carries the grievous punishment! 24 Destroying all things by commandment of its Lord. And morning found them so that naught could be seen save their dwellings. Thus do We reward the guilty folk. 25 We had strengthened them as We have not strengthened you, had given them ears and eyes and hearts; but nothing stood them in good stead, neither their ears nor eyes nor hearts, for they rejected the signs of God, and were seized by what they had mocked. 26