Sin is anything that separates us from God whether it is by omission or commission. Continual willful disobedience is deliberate defiance to our Father and Creator, resulting in separation from Him. We deceive ourselves by thinking we can get by this time or He loves me so He will just naturally forgive me. Sin leads me into darkness,separation and lack of fellowship with my Lord and Savour. When I "walk in the light" I have fellowship with My Lord, our relationship grows into intimacy only because the blood of Jesus purifies me from my sin. It is only when I confess my sins, and choose to walk with Him in His light, that I can no longer experience separation, but enjoy close relationship with my Lord.