The principal source of conflict in the human spirit is the sense of guilt. Psychologists tell us, it is the mysterious feeling of guilt which lies at the root of most people’s disquiet of mind and disturbance of will. On both levels, the sacrament of Confession is the Lord’s great gift to His followers.
Peace of mind is the experience of knowing the truth. We all know that we are sinners. We also know that, as sinners, we have offended God and become estranged from His love in the measure of our sins. How we need the assurance, based on faith, that this offended God is still pleased with us. When Christ tells us that there is greater joy in heaven over one sinner doing penance than over ninety-nine who are just, He is speaking of us who have deserved His rejection. The more often we receive His sacrament of mercy, the more deeply we are at peace.
Peace of heart is the experience of doing the will of God. There is no peace in doing what we want. I know whereof I speak when I say that, doing one’s own will is hell on earth. God wants us to enjoy peace of heart. That is why He instituted the sacrament of Confession. The more frequently we confess our failings, no matter how minor they may seem to be, the more deeply peaceful we shall be. Why? Because if there is one thing that God wants us to admit, and keep admitting, it is that we are sinners who trust in His loving mercy.
Fr. Hardon Archives - The Spiritual and Psychological Value of Frequent Confession