Has it not, then, become plain to those who have inherited the earth in the wake of the former generations that, had We so willed, We could have afflicted them for their sins, (they, however, are heedless to basic facts and so) We seal their hearts so that they hear nothing. 100 Those cities - We relate to you, [O Muhammad], some of their news. And certainly did their messengers come to them with clear proofs, but they were not to believe in that which they had denied before. Thus does Allah seal over the hearts of the disbelievers. 101 And We found no covenant in most of them; and most of them We found ungodly. 102 After those We sent forth Moses with Our signs to Pharaoh and his nobles, but they dealt with Our signs unjustly. Observe, then, what happened to the mischief-makers. 103 And Musa said: O Firon! surely I am an apostle from the Lord of the worlds: 104 so constituted that I cannot say anything about God but the truth. I have now come unto you with a clear evidence from your Sustainer: let, then, the children of Israel go with me!" 105 He answered: 'If you have come with a sign, show it to us if you are of the truthful' 106 So he cast his staff; and behold, it was a serpent manifest. 107 And he drew forth his hand, and lo, it was white to the beholders. 108