Some will say we can write off Genesis 1 to myth. We can say God did not create the earth without hurting the rest of the message. The problem is, Genesis 1 is not the only place in the Bible that claims God's creation. The Bible is full of it, especially the Old Testament. Here is an example from Psalm 33:8-9:
Let all the earth fear the LORD
let all the inhabitants of the world stand in awe of him
For he spoke and it came to be
he commanded and it stood firm.
The Psalmist is saying that, because God created the world, we owe him our reverence and our worship.