Jesus did not create a new nature, he gave us a new one.
But he did not remove the old one. Paul made it clear in romans 7 he still struggled in doing what he wanted.
He understood what true sin was. He became a pharisee who thought he was sinless. to an apostle who considered himself the chief of all sinners.
EG, read this whole post. Do not just scan it, but open your mind.
Just as long as you do not believe we still have the old one, which I think you do believe. To take away our sin, that is actually taking away our sin nature, not adding to it.
2 Corinthians 5:17
Therefore, if anyone
is in Christ,
he is a
new creation; old things have passed away; behold, all things have become new.
Galatians 5:15
For in Christ Jesus neither circumcision nor uncircumcision avails anything, but a
new creation.
Open your mind to distinguish CONTEXT in Romans 7-8. It is about the old law of the Ten Commandments, but the old nature was still there, making it in opposition to God's holy law. All you could hope to do back then was keep the letter of the law which anyone could do with a little will power, but iniquity would still be in the heart, making the secret sin of coveting still breakable, thus breaking the whole law. James 2:10 For whoever shall keep the whole law, and yet stumble in one
point, he is guilty of all." Coveting was mentioned in Romans 7:7 because it can be unseen by anyone around us, and was hard not to succumb.
7 What shall we say then?
Is the law sin? Certainly not! On the contrary, I would not have known sin except through the law. For I would not have known covetousness unless the law had said,
“You shall not covet.” 8 But sin, taking opportunity by the commandment, produced in me all manner of evil desire. Coveting is part of the old nature. So if we covet it can lead to murder or stealing. Or in my husband's case, adultery with the wife of his best friend.
But someone with the Holy Spirit does not have that struggle with coveting. They have a new nature and the Spirit gives life. But the problem in Christianity is not everyone has been born again. Satan doesn't care if you believe in Jesus, just as long as you still sin. Romans 6:15:16; Matthew 7:21-23. Do not be led away believing someone under the New Covenant still has the old nature they had during the Old Covenant, and their sins were overlooked. Romans 3:25. We are under a higher standard and why Jesus said in Matthew 5:20 For I say to you, that unless your righteousness exceeds
the righteousness of the scribes and Pharisees, you will by no means enter the kingdom of heaven.
EG, Romans 8:1-2 is the conclusion and result of the receiving of the power of the Spirit in a new nature over just the knowledge of the Law.
1 There is therefore now no condemnation to those who are in Christ Jesus, who do not walk according to the flesh, but according to the Spirit. 2 For the law of the Spirit of life in Christ Jesus has made me
free from the law of sin and death.
So note that Romans 8:2 (the Spirit) makes Romans 7:14-23 no longer true. And to be saved
now, we MUST have the Spirit, for without the Spirit you are still under the law which you cannot keep with a sin nature - it must be dead, and recreated - therefore, your sins are no longer overlooked, and we will not go to heaven.