۞ AND REMEMBER that brother of [the tribe of] Ad, how - seeing that [other] warnings had already come and gone within his own knowledge as well as in times beyond his ken - he warned his people [who lived] among those sand-dunes: "Worship none but God! Verily, I fear lest suffering befall you on an awesome 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 (of the time of its coming) is with Allah only, and I convey to you that wherewith I have been sent, but I see that you are a people given to 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 bound to destroy everything at its Sustainer's behest!" And then they were so utterly wiped out that nothing could be seen save their [empty] dwellings: thus do We requite people lost in sin. 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