Is it possible that injustices against us are not as dangerous as our reactions to those injustices? If we do not realize the potential inner damage done to us by people’s unfairness, we could let evil grow in us. Think about that: A person “out there” does bad things and the result is evil “in here,” in you.
When those bad things are serious, when your own inner world is threatened with growing anger and discontent, is there anything at all in this world that can quiet the beast more than forgiveness? I do not think so.
Other people’s troubles can become your monsters within if you give them space, feed them, and allow them to grow. Forgiveness shrinks then eliminates those monsters within.
If you think about it, forgiveness helps you retain your humanity, and to even grow in that humanity at a time when others are trying to let the inner monsters out of their cages.