All Christians confess that God created the heavens and the earth. Not all Christians agree that Genesis 1 is a literal description of how God did that. When we follow the literal reading of Genesis 1, the earth was created first: “The earth was without form and void, and darkness was over the face of the deep” (Genesis 1:2). God started his creation work. He created light; he created the expanse of heaven; he created dry land and trees and plants living there. Then we read about the fourth day: “And God said, “Let there be lights in the expanse of the heavens to separate the day from the night”… And God made the two great lights–the greater light to rule the day and the lesser light to rule the night–and the stars” (Genesis 1:14,16).
God is above his creation
This teaches us that we do not have light because there is a sun, but because God gives it to us. It shows us that God is above his creation. Some Christians maintain that Genesis 1 expresses this truth, but should not necessarily be read as a chronology of what was created when. The weakness of this position is that Genesis 1 on first reading does come across as a description, and that in the ten commandments the command to rest on the Sabbath is grounded on a creation in six literal days: “For in six days the LORD made heaven and earth, the sea, and all that is in them, and rested on the seventh day” (Exodus 20:11).
Read as a poem
On the other hand, the strength of this position is that if Genesis 1 is read more as a poem celebrating creation, we do not have to assume that the laws of nature were not at work yet in the beginning of creation. For the earth, day and night, seasons, and place and movement in the universe are all dependent on the sun. Therefore Christians advocating a more poetic reading of Genesis 1 will assume that the sun was created before the earth, because with the current laws of nature earth cannot exist without the sun.
To summarize
The text of the Bible says that the earth was created before the sun. Not all Christians agree that this text should be taken literally. Knowing that our knowledge is limited, it seems best to give each other the freedom to disagree on this. But let us together praise our Creator, and confess our dependence on him.