Light.  "...don't light a candle and put it under a bushel, but on a candlestick...where it gives light to all that are in the house.  Let your light so shine before men, that they may see your good works and glorify your Father which is in heaven."  Matthew 5:15-16

The purpose of light is to be able to see.  To see the world in which we live.  The purpose of light is to cause growth in plant life.  To provide food.  The purpose of light is to warm our world.  And on and on...light has a purpose.  Without it, everything dies.  Light.  Christ is the ultimate light. "In Him was life, and the life was the light of the world." John 1:4

 In Genesis 1:1, God created the heavens and the earth.  All of it.  But something happens, and the writer of Genesis picks up the story in Genesis 1:2.  The earth that God created has become dark, void--or empty--and formless.  And God waits.  How long?  Billions of years?  There is no light reaching the earth.  Light has been blocked by something.  A debris cloud of ash?  Nothing is growing.

The only surviving life is in the water.  That life in the water goes on as it always had, it has not evolved!  It looks today like it looked eons ago.  The dinosaurs are gone.  But not the life in the water.  When we study strata, we see the remains of water life that goes back clear through the ages.  Crickets are crickets.  Sharks are sharks.  Alligators are alligators.  And a zillion other creatures.

 Genesis 1:2b "...and the Spirit of God moved upon the face of the waters."  I don't know what God was doing during all that time.  He doesn't tell us.  But the earth leaves clues in strata.  Things die, and are covered by soil, and their bones become a record in that soil, strata.  The layers are like a time clock.  But when the dinosaurs died, the remains of dinosaurs in strata vanish.  Only the remains of what was in the ocean are preserved--because that is all that is left.

And then, God speaks.  For the first time in the Bible, we hear the voice of God.  The first recorded words of our Creator.  He says, "Let there be light."  Hallelujah.  And because He is God, because He is all powerful, because at His voice the universe exists, the Bible tells us, "...there was light."  God spoke it  into existence.  And He continues to speak light into existence in hearts of mankind.