I thought brother Eli's answer was rather poor. He stated that to learn how to forgive, one must understand that God's response would be to forgive us. In other words, we don't do the forgiving because it is the correct thing to do, but because it will benefit us. This is a selfish way to look at things.

I believe a better answer to the question would be to try to understand WHY the other person may have done you wrong. By understanding the other person's motive, it is much easier to become empathetic to that person and that empathy will allow you to forgive them. Empathy is far more powerful than selfishness and makes forgiving that much easier.

One must remember that we are all God's children and He/She loves us all the same. God wants us to get along and to learn. By learning empathy, we are growing spiritually. There are many things that are not black and white. We need to learn to seek out the grey and discover the many truths that are not immediately evident.

Although what the person may have done to us might not be just nor ethical, if we can see their perspective, we might understand why they may have chosen the path they took. It might be the wrong path to take, but nevertheless, they may have believed justified in taking it. As brother Eli said, we all make mistakes and sin. Most of the time, we don't sin deliberately, but do it because we feel justified to do so or feel like we have no other choice. When we understand the reasoning, we can forgive the person for making poor choices, even when we don't condone the act itself.