They’re not good people. So when they “stir up” things by their attitudes and words — it won’t be pretty. In this verse, they have the whole “city” agitated.
The second line refers to “the wise.” Their attitudes and words have a totally different effect on situations. They have the ability to “turn away anger.”
Every community better have some of these folks, because there’s always going to be plenty mockers!
Actually, it’s much simpler to criticize and ridicule. Really, with just a little practice, anyone can stir up a city!
But it takes a lot more time, energy and character to turn away anger. And the benefits (in this life and the life to come!) make it worth the effort.