Using the NIV, here is the breakdown of what happens to your spirit when you get saved.

To answer the question directly: The “Old Spirit” dies and is removed. It does not “come back,” but a “New Spirit” is put in its place.

Here is the step-by-step biblical proof.

1. Does the Old Spirit die? (YES)

The Bible uses the strongest possible word for this: Crucified.

It doesn’t just get sick or go to sleep; the “Old Man” (your old spiritual identity) is killed off with Christ.

  • Romans 6:6: “For we know that our old self was crucified with him so that the body ruled by sin might be done away with, that we should no longer be slaves to sin.”
  • Galatians 2:20: “I have been crucified with Christ and I no longer live, but Christ lives in me. The life I now live in the body, I live by faith in the Son of God, who loved me and gave himself for me.”

2. Does the Old Spirit it go away? (YES)

Scripture says the “old” is gone and “removed.” It is a replacement, not just a repair job.

  • 2 Corinthians 5:17: “Therefore, if anyone is in Christ, the new creation has come: The old has gone, the new is here!”
  • Ezekiel 36:26: “I will give you a new heart and put a new spirit in you; I will remove from you your heart of stone and give you a heart of flesh.”
    • (God takes out the hard, dead spirit and puts in a responsive, living one).

3. Does it come back? (NO, but…)

This is the most confusing part for believers.

  • The Old Spirit (Old Man): Is dead and gone. It cannot come back.
  • The Flesh (Sinful Nature): Still lives in your body/mind and fights against your New Spirit.

Many people mistake the “Flesh” for their “Old Spirit.” The “Flesh” is the habits, desires, and programming left in your physical body and brain.

  • Galatians 5:17: “For the flesh desires what is contrary to the Spirit, and the Spirit what is contrary to the flesh. They are in conflict with each other…”
    • (Notice there is a war: The New Spirit vs. The Flesh. If the Old Spirit were still there, you would have three parts fighting. But the Bible says it is just two: Spirit vs. Flesh)

Summary of the Swap

PartWhat Happens at Salvation?Bible Verse
Old SpiritDIES / REMOVED. It is crucified.Romans 6:6
New SpiritCREATED. You get a brand new spirit born of God.Ezekiel 36:26
The FleshREMAINS. It stays to annoy you until you die/go to heaven.Galatians 5:17

The Verdict:
You are a New Spirit living in an Old Body (which has the Flesh).
The struggle you feel isn’t your Old Spirit coming back from the dead; it is your New Spirit fighting against the bad habits and desires (Flesh) stored in your brain and body.