In what ways is becoming a Christian becoming an entirely new man / woman?

God has brought us to Himself in Christ, and there is new creation (2 Cor. 5:17). Here there is not one element of the old order, “Old things are passed away; behold, all things are become new.” Old responsibilities, old nature, old relationships, old affections: in Christ all these are gone, and in their stead have come to pass new nature, new responsibilities, new relationships, new affections; a new man, in whom we may well glory, for He is the masterpiece of eternal love.

The man in Christ belongs to a sphere where "old things have passed away" and where "all things have become new." This is truly Christianity according to the thought of God. All in Christianity proper is new; the revelation of God is entirely new; a new life has been manifested; new relationships have been formed; new associations now exist; a new man has been created; everything is heavenly in origin and character, and all our thoughts, desires, feelings, joys and affections, are altogether new. How good for us when we live in the light and power of these things; when we view the old order of things in which we once lived as gone forever from the sight of God, and gone forever for us also. It is true that we have to live still in old creation relationships and circumstances, but we can bring into them the light and character of the things that are heavenly and new.

When we come to Ephesians 4:20-24, we learn how the truth of the new creation is to be brought into our everyday lives. The truth as it is in Jesus is brought out in its three parts: first, "Your having put off according to the former conversation the old man which corrupts itself according to the deceitful lusts;" secondly, "being renewed in the spirit of your mind;" thirdly, "having put on the new man, which according to God is created in truthful righteousness and holiness." As having learnt the Christ, we learned that we were finished with the life in which once we lived according to the flesh, and that the spirit of the mind is renewed in being occupied with Christ and His things. How different are the outlook and thoughts of the Christian as having Christ as his object. Then we have put on the new man; our life now is lived according to the truth of new creation, where all is marked by holiness and righteousness, features that spring from the nature and character of God. What follows shows how very practical the truth is; these great truths are to affect us in every relationship down here, and in every detail of our lives.

In Christ is new creation (2 Cor. 5:17). There “old things are passed away; behold, all things are become new;” new nature, new life, new relationships, new affections. And all these things are of God. The man in Christ is of God, and everything connected with him. In Adam is old creation: old, fallen, sinful, defiled, dead, and lost. In Christ is new, and “as He is, so are we in this world” (1 John 4:17).

But the saints are on an entirely new footing; the ye is emphatic in verse 20. There is the putting off of the old man, and putting on of the new. It is not merely a change of practice (that we shall see in what follows), but there is a thorough setting aside of the old corrupt man; the fresh spirit of the mind, and putting on of the new man (new kainon) created after God in righteousness and holiness of truth. It is no modification or "better ways," as people say, but a new creation; and we have taken this place.

This great truth is doctrinally unfolded in 2 Cor. 5, where we read, "If any man be in Christ, he is a new creature: old things are passed away; behold, all things are become new." (ver. 17) The apostle does not say, "If any man be in Christ he is pardoned — his sins are forgiven — his debts paid." All this is divinely true; but the statement just quoted goes very much farther. It declares that a man in Christ is a new creation altogether. It is not the old nature pardoned, but completely set aside, with all its belongings, and a new creation introduced in which there is not a single shred of the old. "All things are become new; and all things are of God."

This, and nothing else, is Christianity. It is not "the old man" — the first Adam — nature, becoming religious, even though the religion be the profession of the doctrines, and the adopting of the ordinances of Christianity. No; it is the death, the crucifixion, the burial of the old man — the old I — the old nature, and becoming a new man in Christ. Every true believer is a new man in Christ. He has passed clean out of the old creation — standing — the old estate of sin and death, guilt and condemnation; and he has passed into a new creation-standing — into a new estate of life and righteousness in a risen and glorified Christ — the Head of the new creation — the last Adam.

In entire distinction from man in innocency, or man knowing good and evil and being under the power of sin, the believer is of the new creation, and is created after God in righteousness and true holiness. (Eph. 4:24.) His conscience is now God's servant, and in the glory to come will have not a word to say, for righteousness and holiness of truth then will be his native air. There is no return to innocency — to the state in which Satan found man and deceived him; but God makes all things new. The state of innocency in Paradise was not absolute perfection; the state of being as gods, and knowing good and evil, and yet having no power to live to God, was development, indeed, but development into death. The new creation is the knowledge of good and evil, together with the life of God and His indwelling Spirit, and, as a consequence, dwelling in the light and love of the nature of God. This new creation is perfect, and when the people of God are before Him in bodies of glory their state will be perfection.

Verse 22 is rightly translated "having put off" (JND). The old man with its former manner of life, corrupt and deceitful, has been once and for all time put off. No believer can ever again be what he was before conversion, what he was in Adam. He has been renewed in the spirit of his mind: the attitude of his mind has changed. Though the fleshly nature remains in him, this no longer dominates him. There is a new controlling factor: he has put on the new man which is consistent with God's own nature, created in righteousness and holiness of truth. Righteousness is acting rightly in consistency with whatever relationship we may be in. Holiness is the love of what is good and the hatred of evil. But it is the truth of God that decides what is good and what is evil, not merely people's consciences or opinions.

Embracing such a message in faith great moral results at once appeared in them. Divine life was now theirs, and it began to manifest itself. An extraordinary revolution took place in their characters. New life meant a new nature; and a new nature meant transformed characters. Things now appeared in them personally that had never been there before — things not donned outwardly as an article of raiment, but rather produced outwardly as the fruit of the working of life within, as the feathers of a bird or the leaves of a tree. Faith and love and hope were working in their hearts (verse 3).

The one whom the Lord Jesus cleanses is changed, not only on the outside, but also on the inside, when he is born again. The Lord gives him a clean heart, a new nature that hates and loathes and abhors sin, and is never happy if the one in whom that nature dwells has fallen into sin, until he is restored.