Question: "How could there be light on the first day of Creation if the sun was not created until the fourth day?"
Answer: The question of how there could be light on the first day of Creation when the sun was not created until the fourth day is a common one. Genesis 1:3-5 declares, "And God said, 'Let there be light,' and there was light. God saw that the light was good, and He separated the light from the darkness. God called the light 'day,' and the darkness He called 'night.' And there was evening, and there was morning " the first day." A few verses later we are informed, "And God said, 'Let there be lights in the expanse of the sky to separate the day from the night, and let them serve as signs to mark seasons and days and years, and let them be lights in the expanse of the sky to give light on the earth.' And it was so. God made two great lights " the greater light to govern the day and the lesser light to govern the night. He also made the stars. God set them in the expanse of the sky to give light on the earth, to govern the day and the night, and to separate light from darkness. And God saw that it was good. And there was evening, and there was morning " the fourth day" (Genesis 1:14-19). How can this be? How could there be light, mornings and evenings on the first, second, and third days if the sun, moon, and stars were not created until the fourth day?
This is only a problem if we fail to take into account an infinite and omnipotent God. God does not need the sun, moon, and stars to provide light. God is light! First John 1:5 declares, "This is the message we have heard from him and declare to you: God is light; in Him there is no darkness at all." God Himself was the light for the first three days of Creation, just as He will be in the new heavens and new earth, "There will be no more night. They will not need the light of a lamp or the light of the sun, for the Lord God will give them light. And they will reign for ever and ever" (Revelation 22:5). Until He created the sun, moon, and stars, God miraculously provided light during the "day" and may have done so during the "night" as well (Genesis 1:14).
Jesus said, "I am the light of the world. Whoever follows me will never walk in darkness, but will have the light of life" (John 8:12). Much more important than the light of day and night is the Light who provides eternal life to all who believe in Him. Those who do not believe in Him will be doomed to "outer darkness where there is weeping and gnashing of teeth" (Matthew 8:12).