۞ And remember thou the brother of the Aad when We warned his people in the sandhills - and surely there have passed away warners before him and after him - saying: worship none save Allah, verily I fear for you the torment of a mighty Day. 21 They said: Hast come to turn us away from our gods? Then bring upon us that wherewith thou threatenest us, if thou art of the 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 So when they saw it as a cloud advancing towards their valleys, they said: "This is just a passing cloud that will bring us rain." "No. It is what you were trying to hasten: The wind which carries the grievous punishment! 24 Destroying everything by the command of its Lord, so they became such that naught could be seen except their dwellings. Thus do We reward the guilty people. 25 And assuredly We had established them in that flourishing condition wherein We have not established you, and We had appointed for them hearing and sight and hearts; yet their hearing and sight and heart availed them not at all, they became wont to gainsay the revelations of Allah, and surrounded them that whereat they had been mocking. 26