"Who shall lay any thing to the charge of God's elect? It is God that justifieth." (Romans 8: 33)
We cannot ignore this truth enough - God justifies us.
That statement is in the present tense.
Our justification is once for all, and forever:
"But this man, after he had offered one sacrifice for sins for ever, sat down on the right hand of God;" (Hebrews 10: 12)
This truth is still not active enough in people's minds, though, because they are not identifying with it.
We have to understand that we are God's elect, that He has chosen us:
"Ye have not chosen me, but I have chosen you, and ordained you, that ye should go and bring forth fruit, and that your fruit should remain: that whatsoever ye shall ask of the Father in my name, he may give it you." (John 15: 16)
This is not an issue of predestination, but rather of submission:
"What man of you, having an hundred sheep, if he lose one of them, doth not leave the ninety and nine in the wilderness, and go after that which is lost, until he find it? 5And when he hath found it, he layeth it on his shoulders, rejoicing. 6And when he cometh home, he calleth together his friends and neighbours, saying unto them, Rejoice with me; for I have found my sheep which was lost." (Luke 15:4-6)
Repentance is all about letting God save us. Being chosen requires us allowing God to take us. That is all.
Today, God justifies us. No matter what bad thoughts or feelings we may think or feel, especially when we are not aware of them, we accept today that we are justified, and continue to be justified before God:
"For if by one man's offence death reigned by one; much more they which receive abundance of grace and of the gift of righteousness shall reign in life by one, Jesus Christ. (Romans 5: 17)
We can keep receiving this righteousness because God is still justifying us through His Son.
Now, when we understand this unending righteousness, these verses make perfect sense:
"But if we walk in the light, as he is in the light, we have fellowship one with another, and the blood of Jesus Christ his Son cleanseth us from all sin. 8If we say that we have no sin, we deceive ourselves, and the truth is not in us. 9If we confess our sins, he is faithful and just to forgive us our sins, and to cleanse us from all unrighteousness." (1 John 1: 7-9)
Jesus' blood cleanses us, and we are cleansed from all unrighteousness.