۞ 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: 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, "God alone knows when it will come, and I deliver to you the message with which I am sent, but I see you are a people who are ignorant." 23 And when they saw it as a sudden cloud heading for their valley they said: 'This is a cloud that will bring us rain' 'Rather' (he replied): 'it is that which you have sought to hasten, a wind in which there is a painful punishment. 24 Destroying everything by the Command of its Lord! So they became such that nothing could be seen except their dwellings! Thus do We recompense the people who are Mujrimun (polytheists, disbelievers, sinners, etc.)! 25 And yet, We had established them securely in a manner in which We have never established you, [O people of later times;] and We had endowed them with hearing, and sight, and [knowledgeable] hearts: but neither their hearing, nor their sight, nor their hearts were of the least avail to them, seeing that they went on rejecting God's messages; and [in the end] they were overwhelmed by the very thing which they had been wont to deride. 26