۞ 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 delude us away from our gods? Then bring us what you promise us, if you should be of the truthful." 22 He said: The knowledge is with Allah only. I convey unto you that wherewith I have been sent, but I see you are a folk that know not. 23 Then, when they saw the (Penalty in the shape of) a cloud traversing the sky, coming to meet their valleys, they said, "This cloud will give us rain!" "Nay, it is the (Calamity) ye were asking to be hastened!- A wind wherein is a Grievous Penalty! 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 We had established them in that which We have not established you, and We made for them hearing, sight, and hearts, but their hearing, sight, and hearts did not help them a thing, because they disbelieved the signs of Allah. And what they mocked encompassed them. 26