MrWonder,
You say plainly in your first sentence that a born again does not sin:
"This means the person who has been born again has a spirit made alive by the Holy Spirit in the image of Jesus Christ and that spirit does not sin."
These are your words, not mine. Either believers in Christ do sin or they do not.
Than you say:
"The motions of sin are in the unregenerate mind but the spirit-man is complete in Christ Jesus and is one spirit with Him and does not sin."
This is a contradiction of spiritual reality. A believer cannot be regenerated by the Holy Spirit and unregenerated at the same time. James makes it clear a spring of water cannot produce salt water and clear water at the same time.
I do agree with you on this statement:
"It does NOT mean that a Christian never sins - indeed, the Christian is more aware of sin in his life than ever before, but it means the new man created in Christ (his spirit) is sin-free and righteous in Christ."
Than you say:
"The carnal nature is gone forever when we are resurrected in the new body, and thus sin shall never exist on the streets of the New Jerusalem."
Again, this is not possible because the carnal mind or carnal nature in this life is not subject to God's will so that person is a lawless person and according will not spend eternity with Christ. "Rom. 8:6 through Rom. 8:9 (KJV)
6For to be carnally minded is death; but to be spiritually minded is life and peace. 7Because the carnal mind is enmity against God: for it is not subject to the law of God, neither indeed can be. 8So then they that are in the flesh cannot please God. 9But ye are not in the flesh, but in the Spirit, if so be that the Spirit of God dwell in you. Now if any man have not the Spirit of Christ, he is none of his." Even in this passage Paul says it's carnality or spiritually. One or the other not both.
Thus, the carnal mind or carnal nature has to be destroyed this side of the resurrection so the believer can live a blameless in the beauty of holiness.
Don