Man is an Eternal Being
Before make an attempt to define a man, We need to look at the initial idea of his creation. This will give us insight to the General question: Where did man come from ? and the specific question: What is the life span of man?
Where did We come from ?
In my academic background, I am a Biologist, So it is natural for me to look at the work of Darwin, in the theory of evolution but this theory is not enough to explain the origin of man. because it talks about evolution not origin. Plus, evolution still needs a mighty hand to make it happen. Before life evolved, let us look in the beginning
In the beginning, God created the heavens and the earth (Gen. 1:1). Here the bible gives us a series of creations by the creator, God. Then in Gen. 1:26-27, the Bible reveals the project of creation of man.
And God said, Let us make man in our image, after our likeness: and let them have dominion over the fish of the sea, and over the fowl of the air, and over the cattle, and over all the earth, and over every creeping thing that creepeth upon the earth.
This scripture gives a clear understanding of the origin of man and the hint of how we can investigate the nature of man in the attempt to define his life span. To understand the nature of a man, We can look at God since God himself used his image and likeness and a model to reference from when creating man.
Who is God ?
God is a Spirit: and they that worship him must worship him in spirit and in truth.
In this scripture, Jesus gives us a definitive answer to the question of who is God. God is a Spirit. This means that God is not a physical being, he is not a body, he is not a soul, he is not a flesh. God is a spirit.
Image and Likeness of God
Man was created in the image and likeness of God. This means that man is a spirit too.
In his book, How You can be led by The Holy SPirit, Kenneth E. Hagin argues that
Man is a spirit, He has a soul and he lives in a physical body.
The 3 components of man are mentioned by Paul in his 1rst letter to Thessalonians 5:23: Spirit, Soul and Body.
In his letter to Philippians, Paul makes us understand that he desired to depart as a spirit, leaving the body behind and meet Jesus, but he acknowledge that his work was still needed which required him to remain in the body a bit longer.
I am torn between the two: I desire to depart and be with Christ, which is better by far; 24 but it is more necessary for you that I remain in the body
Can a Man, a Spirit die ?
A spirit is eternal, it never dies. Only the flesh dies but the spirit lives on.
In Philippians 1:23-24, Paul makes it clear that he was going to live either in the body or outside the body as a spirit with Christ. This confirms the eternal life of man as a spirit.
This also confirms that reincarnation is a lie, Bible never say a spirit reincarnates. Paul says he wil “DEPART” and be with Christ so he would not be back as a cow or as another person like deceptive theories about reincarnation say.
Man Being a spirit in the likeness of God, he is eternal and cannot die. He lives in the physical body and when this body deteriorates at the point it can no longer host the man's spirit, We say the body of so and so is in the morgue waiting to be buried. Deep down, we know in our subconscious that the real person is gone and the remaining is just the physical shell.
Where will your spirit go from here ?
Jesus loves you and He promises you that if you confess with your mouth that Jesus is Lord over your life and believe in your heart that God has raised Him from the dead, you will be saved. (Romans 10:9) and he will come in your life as He promised that However, the person who unites himself with the Lord becomes one spirit with him (1 Corinthians 6:17), and as you receive Jesus, you be come a child of God according to his promise that: As many as received Him, to them gave He power to become the sons of God, even to those who believe in His name (John 1:12)
For the wages of sin is death, but the gift of God is eternal life in[a] Christ Jesus our Lord.