Understanding day four is critical to understanding Genesis chapter one. That is because it is used to prove a young Earth interpretation and sometimes to demonstrate how the account is false. One primary concern is if day four is not the creation of the sun, moon, and stars, it opens the creation accounts to long periods.We should read the account as a story that tells us about our world, so that we know the literal truth about the creation. We should read for understanding and not to support an agenda. I have no agenda to prove the universe is old or young, how long life has existed on Earth, or to prove or disprove evolution. I simply want to read Genesis as consistently and rationally as I can.