“Confess your faults one to another” (James 5:16). He who is alone with his sin is utterly alone. It may be that Christians, notwithstanding corporate worship, common prayer, and all their fellowship in service, may still be left to their loneliness. The final break-through to fellowship does not occur, because, though they have fellowship with one another as believers and as devout people, they do not have fellowship as the undevout, as sinners. The pious fellowship permits no one to be a sinner. So everybody must conceal his sin from himself and from the fellowship. We dare not be sinners. Many Christians are unthinkably horrified when a real sinner is suddenly discovered among the righteous. So we remain alone with our sin, living in lies and hypocrisy. The fact is that we are sinners!
"But it is the grace of the Gospel, which is so hard for the pious to understand, that it confronts us with the truth and says: You are a sinner, a great, desperate sinner; now come, as the sinner that you are, to God who loves you. He wants you as you are; He does not want anything from you, a sacrifice, a work; He wants you alone. “My son, give me thine heart” (Prov. 23.26). God has come to you to save the sinner. Be glad! This message is liberation through truth. You can hide nothing from God. The mask you wear before men will do you no good before Him. He wants to see you as you are, He wants to be gracious to you. You do not have to go on lying to yourself and your brothers, as if you were without sin; you can dare to be a sinner...
"In confession the break-through to community takes place. Sin demands to have a man by himself. It withdraws him from the community. The more isolated a person is, the more destructive will be the power of sin over him, and the more deeply he becomes involved in it, the more disastrous is his isolation. Sin wants to remain unknown. It shuns the light. In the darkness of the unexpressed it poisons the whole being of a person. This can happen even in the midst of a pious community. In confession the light of the Gospel breaks into darkness and seclusion of the heart. The sin must be brought into the light. The unexpressed must be openly spoken and acknowledged. All that is secret and hidden is made manifest. It is a hard struggle until the sin is openly admitted. But God breaks the gates of brass and bars of iron (Ps. 107:16).
"Since the confession of sin is made in the presence of a Christian brother, the last stronghold of self-justification is abandoned. The sinner surrenders; he gives up all his evil. He gives his heart to God, and he finds the forgiveness of all his sin in the fellowship of Jesus Christ and his brother.
"The expressed, acknowledged sin has lost all its power."
Dietrich Bonhoeffer, Life Together