۞ 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: art thou come unto us that thou mayest turn us aside from our gods? then bring thou upon us that wherewith thou threatenest us, if thou art of the truth-tellers. 22 He said: The knowledge is only with Allah, and I deliver to you the message with which I am sent, but I see you are a people who are ignorant. 23 Then, when they saw it as a sudden cloud coming towards their valleys, they said, 'This is a cloud, that shall give us rain!' 'Not so; rather it is that you sought to hasten -- a wind, wherein is a painful chastisement, 24 It will destroy everything at the bidding of its Lord." So in the morning there was nothing but their empty dwellings to be seen. That is how We requite the sinners. 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