To forbid from evil is the cause of safety

And when a community among them said: "Why do you preach to a people whom Allâh is about to destroy or to punish with a severe torment?" (The preachers) said: "In order to be free from guilt before your Lord (Allâh), and perhaps they may fear Allâh."

So when they forgot the remindings that had been given to them, We rescued those who forbade evil, but We seized those who did wrong with a severe torment because they used to rebel against Allah's command (disobey Allâh).

al a'raaf 164-165