Unhealthy guilt becomes bigger than life. The image of the childhood story of Chicken Little comes to mind. Guilt becomes the experience in which people feel the sky is falling. Yes, we feel guilt over sins, but healthy guilt is one which acknowledges the wrong done and feels remorse, but then is free to embrace the forgiveness that has been offered. Healthy guilt focuses on the realization that all has been forgiven, the wrong has been redeemed.
