۞ 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: "Hast thou come in order to turn us aside from our gods? Then bring upon us the (calamity) with which thou dost threaten us, if thou art telling the truth?" 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 When they saw the torment as a cloud proceeding to their valleys, they said, "This cloud will bring us rain." He said, "No, it is the torment which you wanted to suffer immediately. It is a wind bearing and painful torment. 24 Destroying everything by command of its Lord. And they became so that nothing was seen [of them] except their dwellings. Thus do We recompense the criminal people. 25 And We had certainly established them in such as We have not established you, and We made for them hearing and vision and hearts. But their hearing and vision and hearts availed them not from anything [of the punishment] when they were [continually] rejecting the signs of Allah; and they were enveloped by what they used to ridicule. 26