This is the message we have heard from him and proclaim to you, that God is light, and in him is no darkness at all.  If we say we have fellowship with him while we walk in darkness, we lie and do not practice the truth. But if we walk in the light, as he is in the light, we have fellowship with one another, and the blood of Jesus his Son cleanses us from all sin.   If we say we have no sin, we deceive ourselves, and the truth is not in us.   If we confess our sins, he is faithful and just to forgive us our sins and to cleanse us from all unrighteousness. If we say we have not sinned, we make him a liar, and his word is not in us.

This passage gives us insight into just what we are doing when we make our confession. It’s something we do every week corporately, and most of us confess our sins to God at many other times, whether formally in the context of the Sacrament of Reconciliation with a priest, or informally in the course of our lives when we are suddenly struck with the reality of our failings or sin – those harmful things we did as well as the things we ought to have done and yet failed to do.

John made it very clear that our sin is a fact. We all sin; to deny that is not only to be liars ourselves, but even to call God a liar, because his Word tells us

“There is no one righteous, not even one;
there is no one who understands;
there is no one who seeks God.
 All have turned away,
they have together become worthless;
there is no one who does good,
not even one.” (Romans 3:10-12)

Among human beings, Jesus, and Jesus alone, lived a full life, facing every temptation, and yet did not sin.  As the writer to the Hebrews wrote:
“We do not have a high priest who is unable to sympathize with our weaknesses, but one who in every respect has been tempted as we are, yet without sin.” (Hebrews 4:15)

Therefore the first thing that is clear about our confession is that we are not revealing anything. Our sin is not hidden from God; he is never surprised by the shamefulness of our confession, because it is already known to him. That is why we begin every Mass with the wonderful Collect for Purity: “O Lord, to you all hearts are open, all desires known, and from you no secrets are hid…”

And then that prayer continues with these words: “Cleanse the thoughts of our hearts by the inspiration of your Holy Spirit…” We do not come to God to reveal anything that he doesn’t already know; we come to be cleansed. We come to be healed. We come to bring that which is darkness in us into the blazing light of his Presence, where no darkness can be found. John’s metaphor of Light and Darkness provides a perfect image of what happens when we come to God in our sin. In our shame we are like children hiding in a dark closet, shutting the door against the fearful light of God’s goodness. (And even within that closet, God’s light streams in, piercing through every tiniest crack or keyhole.) But when the door is opened, the darkness is instantly obliterated. No shadow can remain in the closet, and no slightest shade of darkness can taint the brightness of the light.

So it is with our confession. When we come for confession, we open the door of our hearts to the healing light of God’s love, and the shame of our sin is obliterated. “If we confess our sins, he is faithful and just to forgive us our sins,” John wrote, “and to cleanse us from all unrighteousness.” Confession is transformative. Paul wrote:

“Walk as children of light (for the fruit of light is found in all that is good and right and true), and try to discern what is pleasing to the Lord.   Take no part in the unfruitful works of darkness, but instead expose them. For it is shameful even to speak of the things that they do in secret. But when anything is exposed by the light, it becomes visible, for anything that becomes visible is light. Therefore it says,