You emphasize, in the early part of the forgiveness process, trying to understand the offender. Doesn’t this just open us up to excusing the other? After all, if we understand the other, we might develop sympathy for that person and so conclude: “Oh, this person is ok. I will just let it go and move on.”
Understanding the one who offended is very different from excusing the person’s behavior. We can accept a person as having unconditional worth and then hold fast to the truth that the behavior was wrong, is wrong, and always will be wrong despite my understanding the person as a person. In other words, it is important to separate the person and the unjust actions. We try to welcome the person back into the human community as we forgive; we do not then accept the behavior.
For additional information, see Forgiveness Defined.