[Part 3 of what has turned out to be a trilogy on Matthew 5-7]
The claim that God knows the number of hairs on your head is to my mind one of the most striking theological insights that Jesus gave us about God. He actually says this in Matthew 10 and Luke 12, not Matthew 5-7, which is interesting because in both cases he is talking to his closer followers and encouraging them to continue in hard times. Although it is not technically in the Sermon on the Mount it underlies its theology. It makes theological sense that God knows this much because practically all of the Sermon on the Mount depends on God knowing us entirely, down to the innermost thought, and being both Your Father Who Sees in Secret and Your Father Who Will Reward You. But it's so easy to slip out of the practical belief that, oops, just lost a hair, well, God's number just went down by one. It's one of those things that's hard to believe, yet is absolutely crucial.
There's a lot of hairs on a lot of heads in Jesus' day, like the sand on the seashore in the promise to Abraham, an inconceivably large number to human brains. The fact that we can look down orders upon orders of magnitude and see atoms and quarks, then look up orders upon orders of magnitude and see galaxies and superclusters of galaxies, is a difference of degree but not a fundamental difference. Whichever way you look at it, it's beyond you.
It's not too much more of a step to say God knows the numbers of neurons in your brain, and their current state. Come to think of it, maybe that's why we find this hard to believe, because we don't want to believe it. We don't WANT God to know all these random thoughts that run around inside our heads like the Beatles' "Revolution 9". (I heard once that Lennon said that song came closer than anything else to capturing the music he actually heard in his head.) Realizing God knows all that stuff for all of history gives a new perspective on infinite patience and gentleness. Maybe he can stand it because he once experienced it himself.
This comes down to one of the major problems I have with the Intelligent Design argument. If Michael Behe is right and the irreducible complexity of the flagellum required a little divine design the same way as someone might debug a balky program or sketch a blueprint for a car engine, then God stepped in to what Behe would argue is a random, meaningless process and injected a little bit of non-random meaning.
But that means for thousands or millions of years bacteria lived in a random, meaningless universe until God stepped in, played LEGO with the proteins, then stepped out again. If you argue that the flagellum needed a tinkering kind of miracle, then you must argue that the rest of the time the flagellum was non-miraculous. You end up with a universe that is 99.9% non-miraculous with 0.1% of a miracle thrown in. (And, if the percentage of miracles bugs you, it should, because quantifying the miraculous is the logical endpoint of the Intelligent Design philosophy.)
The thing that really gets me is that the 0.1% is constantly shrinking. I've seen it happen, Behe might argue it isn't, but my best professional judgment from decades of study is that it is. If and when we figure out a mechanism for flagellum evolution, then it becomes 0.09%. The mirculous has just been diminished.
The thing is, by focusing so much on the hardest-case scenario and demanding a miracle for it, the ID community inadvertently implies that everything else that is more easily explained is non-miraculous, and therefore random, and therefore meaningless. We end up in a more meaningless universe as a result. You can go with the "Dawkins universe" which 100% lacks meaning or the "ID universe" which 99.9% lacks meaning ... oh wait, I just read another paper explaining another biological mechanism, make that 99.91%.
What can get us out of this dichotomy? Reading closely the words of scripture.
If God knows the very hairs on your head, and by extention the very atoms, neurons, and thoughts in your head, and if in Christ all things hold together (thank you, Paul), then the process that produced thoughts from atoms is not a meaningless mechanism. It is a fascinating interplay of matter, mind, and relationship, held together by its Creator. God is immanent and active -- God is Creator and God is love. He is not absent, but he is patient. Every bond formed, every breath taken, every thought complete is a small miracle.**
Stop before you fall off the cliff of pantheism. God knows all about the hairs on your head but he is not the hairs. I think it's safe to say that God transcends hairs. Also, he is not your thoughts, but you can bring your thoughts in line with his direction, you can bring your thoughts to be "in Christ" as Paul would put it.
Because God knows all these things, you can talk to him, with your vocal cords or without. So what I really want to know of other Christians is not "What do you think about science?" or "How old do you think the earth is?". It's not "What denomination are you?" or "How do you interpet this word or that phrase?". It's a lot closer to the question "Do you pray?" because you gotta talk to God to really see his grace at work, but it's not even that, because I cannot tell when you're really talking to him or when you're mouthing words or dozing off, that's between you and him. What it comes down to is, how well do you love? Loving God is internal, but loving others is external and part of loving God, and it requires daily commitment and dusting yourself off after repeated failure. It requires conformity to the cross found at the heart of creation.
All the stuff about judge not lest ye be judged is part of this. God knows it all, I only know a part. Through a glass darkly, for now. The hope is that the Creator who started it all and who knows every hair therefore loves his creation, and will faithfully see it through from its incomplete, broken state to completion "in Christ." I'm not sure what that means but I'm looking forward to finding out. The path is through the pattern set in his story.
(** I've got more to say that is along the lines of how it is that a BIG disruptive event like the resurrection is a miracle brought about by this God who is closer to you than you are to yourself, but for now it's sufficient to note that, as Stanely Hauerwas pointed out in his Gifford lectures, the resurrection is a miracle that "goes along with the grain of the universe." It is ultimately consistent with the Creator's will and not a violation or suspension of it, and it is necessary.)