۞ And remember the brother of Ad, when he warned his people beside the sand-dunes -- and already warners had passed away alike before him and behind him -- saying, 'Serve none but God! Truly I fear for you the chastisement of a dreadful day. 21 They said: “Have you come to us to turn us away from our gods? Then, bring upon us the scourge that you threaten us with. Do so if you are truthful.” 22 He said, "God alone knows when it will come, and I deliver to you the message with which I am sent, but I see you are a people who are ignorant." 23 And when they saw it as a sudden cloud heading for their valley they said: 'This is a cloud that will bring us rain' 'Rather' (he replied): 'it is that which you have sought to hasten, a wind in which there is a painful 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 And assuredly We had established them in that flourishing condition wherein We have not established you, and We had appointed for them hearing and sight and hearts; yet their hearing and sight and heart availed them not at all, they became wont to gainsay the revelations of Allah, and surrounded them that whereat they had been mocking. 26