UV lights are interesting. They are fun toys to play with, and excellent tools for scientific study. This is because they enable us to see that which is usually invisible. Invisible ink, chemical stains, unique "colors" (sort of like the scorpion you can barely see in the header image, which fluoresces a pleasant green color), all of this, and more, can be seen with the aid of a UV light.
The Bible tells us that God is light, and in Him is no darkness at all (1 john 1:5). As we see from Isaiah's testimony of His encounter with God, this is both literal and figurative. Its more literal sense is difficult to understand. Light, after all, is a material thing, whereas God is spirit. It is strange to think of God, this omnipresent being, as existing in a local sense as well. How can God "dwell in unapproachable light" if He is omnipresent, dwelling literally everywhere (Psalm 139:7-10)? But we don't have to worry about that right now. What we're interested in for the moment is what about the figurative sense?
Throughout the Bible, Isaiah being the example we're rolling with, there are multiple appearances of God to individuals or groups. One thing they all have in common is that the more intense the encounter, the more terrified His target. Look at Isaiah's words. "Woe is me, for I am undone! Because I am a man of unclean lips, and I dwell in the midst of a people of unclean lips." For sure, Isaiah already knew he was a sinner. But having seen God, He became instantly more aware of it.
As an apologist, I deal with many unbelievers, and even professing Christians, who think they would have a thing or two to say to God. "Hey God, if you're so great, why is there so much evil in your world?" "Hey God, you're a bigot, and I hate you." "Hey God, the things I read in your word make me think I'd rather go to Hell than worship you!" Pitiful. Tragic.
NOT.
GOING.
TO HAPPEN.
These people couldn't stand before God and tell Him off. These people couldn't even stand before God. They'll fall prostrate, every knee will bow, and He won't even need to tell them how filthy they are, they'll see their sin as easily as a forensic scientist sees evidence under a UV light.
But God, in His infinite mercy, has not waited until the day we meet Him to reveal our sin to us. He has given us another light. A "lesser" light. A light in the form of a book. Paper and ink, solid, not blinding, that we may know Him, and through the commands we read, we see how unclean we are. We see just why this light is unapproachable: we are the darkness that is not in Him. Though made in His image, we have marred it through sin, and through His word, we can see that long before we are called into His courtroom. And so we repent. We repent, and now we are able to stand before God, even in His light, not of our own will or power, but it is Christ who makes us stand.