4 God saw that the light was good, and he separated the light from the darkness. 5 God called the light “day,” and the darkness he called “night.” And there was evening, and there was morning—the first day. Genesis 1:4-5
So before there was light, there was only darkness. It really didn’t make any difference to God except that it was a shadow of things to come. Jesus was referred to as the Light of the World. The pillar of light shone in the darkness for the children of Israel. God even tells us to let our light shine in the darkness. The contrast of good and evil is implied in light and darkness. In fact, there is no darkness in heaven.
Recently I was working in a manufacturing “cleanroom” where everything is clean and bright. To enter the room I had to put on footies, boots, jumpsuit, hairnet, and gloves. This was all to prevent dust of any sort contaminating the semiconductors they were testing. The first thing I noticed about these cleanrooms, however, was how bright they were. No shadows. Nowhere to hide. No darkness whatsoever. It was bright all day and all night all the time. You didn’t know if it was noon or midnight because there were no windows.
God said light was good because we can see what we’re doing. I for one would much rather drive in the daylight than at night. You can see everything that much better. With Jesus as the light of the world, we do not have to walk around in darkness, fumbling as we go. He has provided a clear path to take. Each day. Every day. Not just when we were saved.