The Spoils of War - 8:38
"Say to those who disbelieve: "If they cease, what they did in the past will be forgiven. If they turn back, the Sunnah (law) of those who were before is valid."
The destruction of previous generations:
The Spider/29:40
And We seized them all with their sins. And We sent upon some of them a mad storm, and a terrible sound seized some of them, and We drove some of them into the earth and drowned some of them. It was not Allah who wronged them; they wronged themselves.