Light was the first thing God spoke in creation. Even before humankind was created, God created light. I believed he created light first so that we’d know that we were created to walk in that light.
Had he created humankind first, our only frame of reference would be darkness and we’d have to become accustomed to walking in light.
“And God said, ‘Let there be light,’ and there was light” (Genesis 1:3)
The writer of Romans mentions that we are without excuse for walking in this light, since he placed an understanding of his eternal power and divine nature in our hearts. Creation is just a reflection of God thinking so highly of us that he uttered these words first: “Let there be light.” He spoke light first on purpose. God wanted His people to experience light so we know and understand the Creator of that light. He wanted us to experience light so we know that darkness doesn’t last always. He wanted us to experience light so we know that “light shines in darkness, and darkness has not overcome it” (John 1:5). Most of all, he wanted us to experience light so we may reflect that in ourselves.