Walking in His Light in Light of Our Sin

1 John 1:8 - 2:2 

8 If we say that we have no sin, we deceive ourselves, and the truth is not in us. 9 If we confess our sins, He is faithful and just to forgive us our sins and to cleanse us from all unrighteousness. 10 If we say that we have not sinned, we make Him a liar, and His word is not in us.
1 My little children, these things I write to you, so that you may not sin. And if anyone sins, we have an Advocate with the Father, Jesus Christ the righteous. 2 And He Himself is the propitiation for our sins, and not for ours only but also for the whole world.

If we walk in the light in fellowship with God in Christ by His Holy Spirit, but say we no longer commit sin, we are self deceived and living a lie.  Though positionally we are righteousness in Christ, we still carry about a core of sinful thoughts and actions which must be mortified day by day (1 Timothy 1:15, Romans 8:12-13).  The hope we have then is that we can still admit (confess) our sin as sin before God, and rely on God’s promise in Christ to forgive and make us clean again as David cried out for in Psalm 51:9-10.  Our Lord is faithful because of His demonstrated character to keep His promises and His mercy by grace when we deserve anything but forgiveness.  Our Lord is also just in that sin’s price cannot be ignored, and is not because Christ paid our penalty for all of our sins forever (Romans 6:10, Hebrews 7:27, 10:10).  No further sacrifice need or can be made; it is finished.  He then cleanses us from our ongoing sin as we confess and forsake it because He is our heavenly lawyer who intercedes before the Judge as the righteous One who appears in our place of sentencing.  He paid the price for all He may call, and His blood sacrifice is eternally effectual and everlasting in its application.  This certainly does not give us the right to go on sinning, just as we cannot say we have not nor continue to commit sin.  No, we are instead called to follow Him in renewing of our thoughts and hearts to be conformed to Christ as we choose to not sin, leaning on His Spirit to put to death these desires of things we want, pleasures apart from God we crave, and the pride of our own accomplishments (1 John 2:15-17), seeking to do God’s will instead out of thankful obedience to God’s glory and good pleasure.