The physical mechanics of the genetic perpetuation of the sin nature in man can be found in a few good embryology textbooks, though it is not generally understood by the world how they apply to this specific spiritual truth. For the purposes of growth, repair and replenishment body cells divide by a process called mitosis. In mitosis one cell with 46 chromosomes divides into two with each new cell then identical to the original, each having 46 chromosomes.
However, in reproductive cells, a more specialized process called meiosis produces the male sperm and the female ovum. In meiosis one cell with 46 chromosomes divides into two cells, but each new cell contains only 23 chromosomes. Are you still awake? You might want to get up and walk around a little or stretch, maybe throw a little cold water on your face.
With the male, one cell with 46 chromosomes divides into two cells having 23 chromosomes each. Then both of these new cells with 23 chromosomes each divide again into two more cells, again with 23 chromosomes. The result is that from one original cell with 46 chromosomes come four mature sperm cells with 23 chromosomes each. So far, so good. Now it gets interesting.
In the female the process of meiosis is different. It has two stages like male meiosis. But, while meiosis in the male produces four sperm cells, meiosis in the female produces only one ovum or egg. This is called oogenesis. Here, one cell with 46 chromosomes divides into two cells with 23 chromosomes each. But, only one cell remains intact, the other disintegrates. The surviving cell with 23 chromosomes then divides again into two new cells with 23 chromosomes each. Again one cell remains and the other disintegrates
Now we get down to the really pertinent part of this whole (and I hope not too confusing) discussion. In each cell that disintegrates cellular material called polar bodies concentrate or polarize themselves on one side of the cell before the division takes place. After the cell divides, the one with the concentration of polar bodies is the one that disintegrates. When the two stages of division in oogenesis are completed, the one ovum produced by this process is completely free of polar bodies.
This process is God's ingenious way of cleansing the female ovum of the contamination of the sin nature that is a part of every other cell that makes up the human body, whether male or female. From this we must draw several conclusions. The first is what we have already alluded to earlier in the fact that scripture tells us that we are all possessors of Adam's sin. That it is a part of our physical makeup and passed on from generation to generation by the man starting with Adam is clear when you consider the difference illustrated by the male and female reproductive systems. In the male, all four mature sperm cells produced contain the exact same makeup, therefore, the same contamination as the original, contamination that is immediately passed on to the uncontaminated female ovum at conception!!! The exclamation points are to get your attention and let you know I'm getting excited about this, because I know where it's leading.
The second thing is that all this boring talk about cells, chromosomes and polar bodies illustrates God's provision to fulfill His promise of the coming of the Christ through the "seed of the woman" in Genesis 3:15. In oogenesis God provided the way for the Son of Man to enter the world through a physical birth with a human mother and be born free of the contamination of the sin nature, yet in a physical body. Make no mistake about this, in Mary a real conception took place, but no man was involved. It was the Holy Spirit that made it possible (Matthew 1:20, Luke 1:34, 35) for the Lord to be born a perfect, sinless man, absent Adam's sin, the only One qualified to go to the cross as our substitute. Mary had a sin nature like everyone else. But, because she was a woman, she could not transmit it to her progeny. After Christ was born she delivered six other children by her husband Joseph through normal procreation. All six were born spiritually dead with a sin nature passed on to them by their father.
At this juncture I should probably just move on. But I can't pass up the opportunity to tear down a few religious concepts. The idea that Jesus' sinless perfection is somehow connected to Mary's virginity is ludicrous at best. One has absolutely nothing to do with the other. The idea that God would have to depend on human merit to accomplish His plan is nothing more than religious arrogance and ignorance. Mary was a sinner in need of a Savior, not unlike any other woman who ever lived. She was condemned as soon as she drew her first breath, just like everyone else. And while I have no intention of diminishing her special place in history and the favor God showed her, I can't elevate her to a prominence that exceeds even the Lord Himself as some do.
The fact is her virginity was only a sign, a signal to all who awaited the coming of the Holy One (Isaiah 7:14). If it had not been for the prophecy requiring the mother of the Lord to be a virgin, this provision of God would have allowed Him to be born to any woman at any time providing she had a healthy, functioning reproductive system to produce the pure egg. And if there can be any question regarding what God thinks about depending on us to help Him carry out His plan, consider Isaiah 64:6, 7.
Because we have all become like one who is defiled and unclean, even our best efforts before God are like filthy rags to Him. We're so frail and here for such a short time and it is our own depravity that carries us like a strong wind far away from God's favor. No one calls Your name and there are none that struggle to embrace You. And so Your face is hidden from us and we are left only to the consuming power of our own sin.
I know there's a sermon here somewhere, but I'll stick to the subject. The KJV uses the term "our righteousnesses" where you see "our best efforts" in the verse above. Both are a reference to self-righteousness (see Philippians 3:9). What follows describes God's attitude towards self-righteousness or human effort. He sees them as "filthy rags". Here, the word translated "filthy" is the Hebrew ed and means, "to set a period (of time)". In the context of the verse it is used to illustrate the woman's monthly menstrual flow. In other words, God considers our self-righteousness to be right up there on the same level of rags used by women to control the flow of blood from their monthly period.
Now you might be wondering why I bring this up at this particular time, so I'll tell you. Remember back when we were talking about oogenesis and how every time a cell would divide, the cell with the polar bodies (the physical contamination of the sin nature present in every cell) would disintegrate? The menstrual period is the means by which the material from these disintegrated cells is sloughed off through a discharge of blood from the uterine wall. Every month the woman discharges a small but significant portion of the sin nature that resides in her body. The illustration in the verse above is simply comparing our best efforts to our own sin. To God there's no difference. No real righteousness exists but His.
The full article can be found on Ken's web site at this link: Grace, Faith and the Plan of God