Some things are simple by way of being uncomplicated; others are simple because they are familiar. No one can say that the human body is uncomplicated, but everyone must admit that it is the most familiar thing in our existence. Few of us have a detailed understanding of how our bodies function, except in the plainest of ways: ingesting, digesting, eliminating, breathing, sweating, and so on. It is not necessary to understand these functions. Our performance of them is largely autonomic.
We learn our bodies from the outside in, and from the inside out, by direct experience of them. This experience is intimate; we are more likely to say, "I am sick," than to say, "I have a sick stomach." The experience of sickness, as well as the experience of well-being, is intensely personal. Because my head hurts, I hurt.
I have a vested interest in every portion of my body. The reason for this self-preoccupation is not that I have a body, but that, in the most profound way, I am my body. That is what's simple. This puts me in a bind, because the basic fact about me as a human body is that I am going to die. That is what bodies do.
Those who know me as a Christian preacher may be shocked at this materialist, even reductionist, view of the self. But remember, I am wielding Ockham's razor in this series, ridding myself of the unnecessary to grasp the essential truth: in this case, about the human body. if we fudge on the fact that we are part of the natural order-- bodily, organic, tangible creatures destined to die—our willful misunderstanding will lead us away from the hope of eternal life as offered by the Christian gospel into a shadowy hope for an endless earthly life, where our biggest victory will consist in outliving our pensions, or an even vaguer hope about the mmortality of the soul.
As part of the natural order, we will die. When we die, as Ben Franklin cheerfully pointed out, we become food for worms. The Bible preaches resurrection, not immortality. There is a difference.
We are food for worms, but God is much more. He gives life to our mortal bodies when we live, and may raise us from the dead after we die. We may delay death for a while and prevent some accidental deaths and cure some potentially fatal diseases, but we don't really want to keep death from happening.
We aren't designed to live forever in this body. Where would we put everybody? We take our turn at life, and eventually we take our turn at death.
Whether we take our turn at resurrection is not up to us, but up to God. In the Apostles' Creed, Christians do not affirm the immortality of the soul, but an everlasting life that follows the resurrection of the dead.
So I wouldn't trust another version. You don't have immortality in you, and neither do I. It was the pagan Greeks of ancient times who started that rumor, not Jesus and his apostles.