You have explained that we are the same person after we’re saved as we were before-hand. How do you explain the “new creation” that the Bible says we become in Christ?
Since it is Paul who speaks of the “new creation” or “new self,” we must understand how Paul’s theology is categorized, so to speak. Throughout all of Paul’s letters, the core of his theology can be divided into two categories: That which pertains to the Flesh on one hand, and that which pertains to the Spirit on the other. So, when Paul speaks of certain things we must first decide into which category the subject falls. Concerning our subject – the New Creation (2Cor. 5:17; Gal. 6:15) or the New self (Eph. 2:4; Col. 3:10) – it is not in the flesh which this newness occurs, but the spirit of a person.
When we receive Christ, we are not a new person (in the flesh), for we are just as we were before. This is why under the category labeled “flesh,” Paul places subjects like sin, Law, and death, etc. (Rom. 7:5, 25; 8:3, 5-8, 12-13). It is the killing power of the cross which the flesh must suffer. Paul says, “I know there is nothing good in my flesh” (Rom. 7:18).
When Christ took on flesh, it was “hypostatic;” that is, His divinity and His humanity never mingled. The two natures aligned side-by-side, as it were, but they never became a “new creation” (that would defeat the purpose of the redemption for humanity).
On the other hand, when the Holy Spirit enters into us, He mingles Himself with our spirit (non-hypostatic) and what is produced is a “New Creation” (Our spirit + the Holy Spirit = a “New Creation” in us; though, still not a new nature). Our flesh is not affected by this union. Incidentally, the resurrection of the dead is for the redeeming of the flesh. What would be the point of a resurrection if the flesh were a “new creation” already? In fact, according to the standards of the “new creation,” the flesh would never die! Is that not the reason that God removed Adam and Eve from the Garden of Eden; so that they would not eat of the Tree of Life and live forever?
So what we have, here, is the place between the “now” and “not yet.” We are now “New Creatures” in the spirit (Rom. 8:4, 9; 13:4; 1Cor. 3:1) – humanity with spirit-mingled divinity. However, we are “not yet” fully redeemed in that divinity because our flesh still dies. One day, and soon, we will enter full redemption at His “parousia” (His appearance and presence) when He comes for what and who are His (the Resurrection of the Dead).
I cannot end this without reminding us that, since our “Old Self,” which falls under the “flesh” category, is not affected by this “New Creation” or “Self” we must crucify it with its desires (Rom. 6:6; Gal. 2:20; 5:24; 6:14). (See “Cruciform” entry for more details on this subject.)