I think this is significant.
Why would God include [specific] knowledge about the "upper" water in scripture? Why would He want us to know about the separation of the "waters" into the "upper" and "lower" waters?
Why did God say "the evening and the morning was the first day"?
Flat earth defines "one day" as sunrise to sunrise.
The SUN DID NOT EXIST on the first day.
That alone proves that flat earth is a lie.
"The evening and the morning was the first day" was the day that God caused the EARTH TO START SPINNING.
That means that the bible defines "one day" as one complete revolution of the earth on it's axis.
It takes ONE DAY, 24 literal hours, for the earth to make a complete revolution.
This blows Flat Earth and Gap Theory straight out of the water.
Have the flat earth Christians been taught how to handle this argument?
Probably not because I have never ran across another person on this planet who could explain how "the morning and the evening was the first day" is even possible BEFORE the sun had been created. I didn't know either until God showed me a few minutes ago. So in that respect I'm thankful you started this thread.