۞ 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 turn us away from our gods? Show us that with which you threaten us if you are truthful". 22 He said: "The Knowledge (of when it will come) is only with Allah: I proclaim to you the mission on which I have been sent: But I see that ye are a people in ignorance!".. 23 Then, when they saw it as a dense cloud coming towards their valleys, they said: "This is a cloud bringing us rain!" Nay, but it is that (torment) which you were asking to be hastened! a wind wherein is a painful torment! 24 It shall annihilate everything by the command of its Lord. Wherefore they became such that naught could be seen save their dwellings Thus We requite a nation of the culprits. 25 And yet, We had established them securely in a manner in which We have never established you, [O people of later times;] and We had endowed them with hearing, and sight, and [knowledgeable] hearts: but neither their hearing, nor their sight, nor their hearts were of the least avail to them, seeing that they went on rejecting God's messages; and [in the end] they were overwhelmed by the very thing which they had been wont to deride. 26