The focus of this study is one of the most misinterpreted passages today. This passage is taught to be describing those who have been washed by the water of regeneration, but this is entirely incorrect. This passage, when correctly interpreted, describes those who have been born of the Spirit, or who have converted to a life of obedience to God, having put away or subdued their old man. In order to properly understand this passage, we must first look at the passages which lead up to this statement by Paul.
2 Corinthians 5:15 And [that] he died for all, that they which live (Greek “zao” meaning “are efficacious” – they which have the capacity to live) should not henceforth live (manner of life) unto themselves, but unto him which died for them, and rose again.
And because He died for all his people, those which are efficacious (have the capacity to live) should not hereafter continue a manner of life which is for their own purpose, but instead for the purpose of him which died for them and rose again. (Personal Translation)
When a person is regenerated, he is given the capacity to comprehend spiritual things. In this passage, Paul builds upon that truth, teaching that this type of person should not continue living for himself like he did before regeneration. Instead, the regenerate person should exercise this new capability to live his life in accordance with the purpose of Christ.
2 Corinthians 5:16 Wherefore henceforth know we no man after the flesh: yea, though we have known Christ after the flesh, yet now henceforth know we [him] no more.
For that reason, from this point forward, we cannot differentiate the regenerate from the rest, when they live according to their carnal nature: nevertheless, we can distinguish Christ according to one’s behavior, yet from now on we cannot distinguish Christ any further. (Personal Translation)
Because the regenerate can be in either of these two conditions, it is impossible to know if a person is regenerated by observing his behavior if he has not yet converted to living for Christ. He may not exhibit any characteristics, or he may only exhibit a few characteristics that could be discerned as one converted. Therefore, we can only know that a person is regenerate when he manifests Christ like characteristics, and not by any other means.
2 Corinthians 5:17 Therefore if any man [be] in Christ, [he is] a new creature: old things are passed away; behold, all things are become new.
Therefore, if any man is in Christ, he is a new kind of person, he is uncommon, his behavior has changed, he is established upon a firm foundation, his priorities have changed, he no longer lives for himself, but for Christ, the old man being subdued; observe, many things about him are different. (Personal Translation) Therefore, if a man has converted to Christ, he is a new person. He will be different than he was before having noticeable changes in his character. He will be established, unlike before, desiring to be a good and faithful servant. When a person is regenerated, he does not immediately manifest the internal change that occurs during regeneration. The person is not even aware of this change until the new man begins to war against the old man. It is not until the person chooses to convert from his sinful ways and live his life in accordance with the guidance of the Holy Spirit, is he considered to be a new creature. If the person has truly converted, he has put away that which was of the natural and has taken hold of the new which is spiritual. He has begun subduing the old man and its control over him, allowing the new to take the lead. He has become a new person, and according to scripture, has set himself apart from those of unrighteousness, and considered a peculiar type of person, and a member of the royal priesthood of God.