Science in the Bible: Light Moves, Darkness Doesn’t

Where is the way where light dwells? and as for darkness, where is its place?  Job 38:19

I checked out what the Easy-to-read Version had for this verse.  It just said, “where does light come from, where does darkness come from?”  Is that accurate to what the Hebrew says?

This verse is recording some of the words of God Himself just after He started answering Job.  Let’s see if He knew what He was talking about!

The word “way” for light is often used to mean “road” or “journey.”  It is also often used to mean ‘life style’ like “the way” of the righteous.  It is an active word.

So, is light active?  Does it have a “way” or “road”?  Sure it does!

Everyone knows that light is the fastest moving thing there is.  We see the lightening a number of seconds before the sound gets to us in distant strikes because sound only travels 1220 km/[760 miles] per hour at sea level.  Light travels (check out the cool picture on that link) in a vacuum at 299,792.5km [186282.4 miles] per second (ps).  There are 3,600 seconds in an hour, so light has gone over a billion kilometers by the time sound has gone 1,220 kilometers.  That’s fast!

In air, light slows down a whole whopping 90km [56mi] ps.  Through water it slows down a lot more to 225,000km [139,808mi] ps.  And through a diamond?  It creeps along at only 125,000km [77,671mi] ps!

So, we know that light is on a really fast journey all the time.  What is the “way” it is on?

Light usually acts as a wave.  The illustration on the “Light travels” link shows this nicely.  It can be slowed down, squashing the waves closer together. It also travels in a straight line unless it passes through something.  This is what causes shadows.  The light can’t get through you (or other opaque things), so it leaves a void behind you.

Light can be bent by transparent things, though, like glass or water.  You’ve seen this with your straw in a glass of water.  The straw looks much bigger and appears to come out at a different spot through the water.  This is called refraction.  It is interesting enough to keep you from focusing on your grumbly tummy at a restaurant, but doesn’t change anything.  But for a spear fisher (or fishing bird), understanding the refraction power of water is very important!

Underwater Rainbow

Rainbows work by bending light as well.  God designed the different wavelengths (colors) of light to bend more or less.  When white light passes through a prism, the purple gets bent the most and red the least.  This allows the light to spread apart so we see each color on its own.  I think that was very sweet of God, myself. 🙂

As for darkness, does it move?  Is is a substance we can study?  Much as scientists today talk about “dark matter,” they use that name because they can’t study it, just make guesses about its existence.  Darkness does indeed have a “place.”  It is everywhere that light isn’t!

And God saw the light, that it was good: and God divided the light from the darkness.
And God called the light Day, and the darkness he called Night. And the evening and the morning were the first day.  Genesis 1:4,5

Cool online activities using light:  The Science of Light: Laws of Light activities