I’ve heard people scoff at the creation account right from the start when God says, “Let there be light.” They say how ridiculous is this Bible you read it says here God created light in verse 3 but he doesn’t create the sun or starts until verse 14! There is an easy explanation for that, God is creating photons in verse 3. Surely those scientific minded types that scoff at the Genesis account knows about photons so even if God had created the sun on day 1 if there were no photons the nuclear reaction that lights our sky would have not been a light at all. Then in verse 4 God programs the photons, they will be separate from the dark. There is a difference between light and a light source. On day one God creates light, and on day 4 God creates natural light sources.
So what was the source of light on day 1 of creation? It was God himself and all his glory. Revelation 21:23 tells us about the new creation, “The city does not need the sun or the moon to shine on it, because the glory of God lights it up, and its lamp is the Lamb.” This new creation spoke of in Revelation does not need natural light sources, it has a super natural light source. I believe it was the same during the first creation.
So despite what some people may say, the Genesis account isn’t indefensible.