Sin permeates every area of a person's life even that of a believer. There is no human fathoming of the depravity in which we all sink.
What our Savior did by taking upon Himself our curse (as Galatians 3 states) that we who believe, though we sin, are no longer cursed. "There is now therefore no condemnation..." (Romans 8).
Does that mean that Christ was no longer innocent? No! He remained without sin, the pure and satisfactory offering to God.
How then are we free from the sin that some teach must be paid for. First remove the thinking that some price for sin had to be met and look at Romans 6 for an answer:
5For if we have been
united with Him like this in His death, we will certainly also be united with Him in His resurrection.
6We know that our
old self was crucified with Him so that the body of sin might be rendered powerless, that we should no longer be slaves to sin.
7For
anyone who has died has been freed from sin. 8Now if we died with Christ, we believe that we will also live with Him.
9For we know that since Christ was raised from the dead, He cannot die again; death no longer has dominion over Him.
10The death He died, He died to sin once for all; but the life He lives, He lives to God. 11So you too must count yourselves dead to sin, but alive to God in Christ Jesus.
If Christ had not died, then sin would remain with power. but the blood cleanses us from all unrighteousness, and the death renders sin as having no authority or power.