First Light
Some people claim a contradiction related to the creation of light. God created light on the first day, but did not create the sun and stars until day four.
Day 1
"And God said, 'Let there be light'; and there was light. And God saw that the light was good; and God 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, one day." Genesis 1:3-5
Day 4
And God said, "Let there be lights in the firmament of the heavens to separate the day from the night; and let them be for signs and for seasons and for days and years, and let them be lights in the firmament of the heavens to give light upon the earth.' And it was so. And God made the two great lights, the greater light to rule the day, and the lesser light to rule the night; he made the stars also. And God set them in the firmament of the heavens to give light upon the earth, to rule over the day and over the night, and to separate the light from the darkness. And God saw that it was good." Genesis 1:14-18
But humans are quite capable of creating light by various means (with fire, electrically, and chemically), and there is no reason to believe that an omnipotent God could not create light independently of the heavenly bodies. The fact that the Bible doesn't record the source of the pre-solar light is irrelevant.
Something to keep in mind when considering these passages about light is that visible light only comprises a portion of the entire wide spectrum of light, or electromagnetic energy. Light consists of photons, and we refer to infrared and ultraviolet as "light", but the spectrum extends beyond ultraviolet and infrared into X-rays, gamma rays, microwaves, radar, and so on. [3]
People have proposed a number of possible sources of light:
Invention vs. Application - some interpret the activities on day one to be those of an inventor who developed the reactions to produce light. Then on day 4 that invention was applied to the creation of the solar bodies that provide light today.
Universe Was Filled With Light - Cosmologists working with 'Big Bang' calculations indicate that a massive presence of photons would have crossed the entirety of the universe during the initial seconds of universal expansion. This would in fact have 'lit up' the entire universe, all at once. "...and there was light." [4]
Sonoluminescence - Sonoluminescence is the process by which acoustic energy is turned into light. This is done by introducing a frequency to water while an air bubble is present. The light produced actually comes from this bubble.[5][6] Light could have been accomplished this way during the creation week when the earth was just a sphere of water before land appeared.
The Light Came From God - God is often referred to as light. And because light that comes from God would be eternal just like God, it would know no bounds of time and could travel to the ends of space instantly.