۞ 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: Have you come to us to turn us away from our gods; then bring us what you threaten us with, if you are of the truthful ones. 22 He said, 'Knowledge is only with God, and I deliver to you the Message with which I was sent; but I see you are an ignorant people.' 23 Then, when they beheld it as a dense cloud coming toward their valleys, they said: Here is a cloud bringing us rain. Nay, but it is that which ye did seek to hasten, a wind wherein is painful torment, 24 It shall annihilate everything by the command of its Lord. Wherefore they became such that naught could be seen save their dwellings Thus We requite a nation of the culprits. 25 And indeed We had firmly established them with that wherewith We have not established you (O Quraish)! And We had assigned them the (faculties of) hearing (ears), seeing (eyes), and hearts, but their hearing (ears), seeing (eyes), and their hearts availed them nothing since they used to deny the Ayat (Allah's Prophets and their Prophethood, proofs, evidences, verses, signs, revelations, etc.) of Allah, and they were completely encircled by that which they used to mock at! 26