I always say that if a person is steeped in negative thinking, even such thinking about other people, then he needs something to disturb him to get him out of his negative thought pattern. If you agree with this, what is a good disturbing situation in your experience that can jolt a person out of negativism?
I think your expression “something to disturb him” is very interesting. What you mean, I think, is something to get the person’s attention in a powerful way. Yes, in my experience I have seen this “jolt” as you call it and it is this: an inner pain that becomes uncomfortable and motivates the person to do something about that pain. Carrying the weight of continual negative thoughts can lead to an abiding sense of anger that turns to resentment. The resentment then can turn on the one harboring it. Resentment can turn to fatigue, restless sleep, a lack of exercise, and a general pessimism about people. This kind of accumulated pain eventually can “jolt” a person into reality: I must do something about this pain. It is here that some people come to realize that their negative symptoms point back to being treated unjustly, being angry, then overly angry, and then miserable. It is at that point that many are willing to consider forgiveness as a fresh response to the original injustice……and to the inner pain that has developed as a result of the injustice.
For additional information, see Why Forgive?