Fatigue is the faithful companion of a grudge. At the end of each day you will collapse in exhaustion, wondering why you feel so fatigued. It is because you are wasting great amounts of unconscious energy maintaining your grudge. Releasing this grudge through forgiveness will result in a brand new surge of emotional and physical energy. This is not to say that everyone who is tired at the end of a hard day's work is harboring a grudge.
Weariness is a symptom of an unforgiving spirit, just as a rash is a symptom of poison ivy.
All rashes do not indicate poison ivy, but a person infected with poison ivy will have a rash. All exhaustion does not indicate a buried grudge, but if you've got a grudge, there is a good chance you'll experience fatigue. A grudge usurps God's rightful role. The ultimate sin in an unforgiving spirit is that we take God's authority from Him. God, and God alone, has the right to condemn men and women.