۞ 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 in order to turn us away from our Gods? Therefore bring upon us what you promise us, if you are truthful.” 22 He said, "Knowledge [of its time] is only with Allah, and I convey to you that with which I was sent; but I see you [to be] a people behaving ignorantly." 23 Then, when they beheld it as a dense cloud coming toward their valleys, they said: Here is a cloud bringing us rain. Nay, but it is that which ye did seek to hasten, a wind wherein is painful torment, 24 destroying everything by the commandment of its Lord.' So in the morning there was naught to be seen but their dwelling-places. Even so do We recompense the people of the sinners. 25 And We had established them in that wherein We have not established you, and We appointed for them hearing, and sight, and hearts; and yet their hearing, their sight and their hearts availed them nothing, since they denied the signs of God, and they were encompassed by that they mocked at. 26