Everyone has to start somewhere. When God began His creation, He started by making light and then separating the light from the darkness (Gen 1:2-5). From the very beginning one thing was separated from another. The Word points out that He made the light and saw that the light (not the darkness) was good.
By its very nature, light is the opposite of darkness, and separation must necessarily exist. Note that God did not create infinitely varying shades of gray. He did not glorify Himself in gray areas. The glory of the Lord that we see in creation’s 1st day was the light.