The Or Hachaim (Devorim 13:18) states that mercy, which is essentially a suspension of absolute justice, is granted only to those who are merciful towards others.

Many times we may feel justified in bearing grudges toward people who have offended or harmed us. In our anger, we are unlikely to consider that there may have been mitigating circumstances in their behavior.

Even if we think we are right, or better yet, even if we are in fact right, we should think about how we wish to be judged ourselves. We always seem to have ample explanations to justify our actions. We should grant this courtesy to others.

If we hope to be forgiven, we must learn to forgive.