۞ 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, 'What, hast thou come to pervert us from our gods? Then bring us that thou promisest us, if indeed thou speakest truly.' 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 So when they saw it as a cloud appearing in the sky advancing towards their valleys, they said: This is a cloud which will give us rain. Nay! it is what you sought to hasten on, a blast of wind in which is a painful punishment, 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 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