Foundational Theological Presupposition – God designed and made the human body. Because he made it, it’s the best body possible for it’s God-given purpose. Because he designed it, there’s a thinking in behind the design that – if we can grasp it – can teach something about who God is. The kidney, therefore, as a unique part of the body, has something special to say about who God is; something different than the heart, lungs or liver. What is that?
And here’s where I’m stuck. When I asked a nephrologist/sermon researcher/friend about the nature of the kidney, he responded in part with this, “What really happens is 1,700 L [of blood] are seen by the kidney [daily], 180 L get through the filter inside the Nephron, then the good stuff that is needed gets taken out and you are left with anywhere from 0.5 -2.0 L per day of waste.”
The kidney removes toxins from the blood by filtering the good out (via the nephron – which we, incidentally, have a total of 60km of in our kidneys) and puts that good back into the system. Kidneys filter out the good stuff and allow the bad stuff to flow through the bio-system and out of the body. And this is where I’m stuck… “What’s best about a system that does it’s filtering this way; filtering out the good for re-introduction back into the blood, as opposed to filtering out the bad for removal?”
One thought is that this way of filtering never requires a filter change. Oil filters – which capture the bad, storing it in the fibres of the filter – need to be changed regularly. Kind of hard to do with a kidney. But there’s something more that I can’t see yet… there’s something ‘just right’ about this way of removing toxins from the system, that can teach me something about how God’s Holy Spirit removes toxins from our systems (individually) and our system (corporately and cosmically). What’s right about taking what’s already right and feeding it back into the system? And what does this say about who God is?