How do we know forgiveness is guaranteed when we confess our sins?

The guarantee of forgiveness comes from God's character, specifically His faithfulness and justice. In 1 John 1:9, we see that God is committed to fulfilling His promise: 'If we confess our sins, he is faithful and just to forgive us our sins.' This guarantees that God not only listens to our confessions but actively responds with forgiveness based on the atoning work of Christ. His justice is satisfied through Jesus, who bore our sins. Thus, forgiveness is not based on our merit but solely on His grace, ensuring every repentant heart can rest assured in His promise.