When God saves someone, all their sins are paid for past, present and future, they are in a sinless state:
"Whosoever is born of God doth not commit sin; for his seed remaineth in him: and he cannot sin, because he is born of God." - 1 John 3:9.
However, evidence of the new birth will show an ongoing desire for mercy, communication and regret of sin:
Psalm 32:5 - I acknowledged my sin unto thee, and mine iniquity have I not hid. I said, I will confess my transgressions unto the LORD; and thou forgavest the iniquity of my sin. Selah.