What's your two cents on this?

One of the reasons I don't believe the Bible is 100 percent authentic is because it's hard to believe that the Earth was created and had light on it a day before the Sun was created. How could there be light without the Sun? Even if God is light, why would he have to say "let there be light" in order for there to be light, and where was the light coming from before he created the Sun? Did it start coming from God when he said that? I suppose this may be one of those, " doesn't make any sense or logical reasoning, but we must have faith it's true" kinda situations.