۞ 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 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, "Only God has the knowledge (of the coming of such torment). I preach to you the message that I have brought, but I can see that you are an ignorant people". 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 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 indeed given them the means which We have not given you, and made ears and eyes and hearts for them; so their ears and eyes and hearts did not benefit them at all because they used to deny the signs of Allah, and the punishment they used to mock at encompassed them. 26