Barbarian notes that early Christians argued that it was absurd to talk of mornings without a sun to have them.
In every language I've heard about, "morning" means when the sun appears in the east. It doesn't mean "a big light in the sky."
Revelation 21:23-25
23And the city had no need of the sun, neither of the moon, to shine in it: for the glory of God did lighten it, and the Lamb is the light thereof.
24And the nations of them which are saved shall walk in the light of it: and the kings of the earth do bring their glory and honour into it.
Nothing about morrning...
25And the gates of it shall not be shut at all by day: for there shall be no night there.
Ah, so there won't be mornings. Just light all the time.
The scriptures conclude that a "day" is when the overwhelming presence of light falls upon the land.
No. It means "when the sun appears in the east." "Big light" doesn't translate to "morning."
The sun does not define a day.
But the point is, it does define "morning."
morn·ing
?–noun
1.
the first part or period of the day, extending from dawn, or from midnight, to noon.
2.
the beginning of day; dawn: Morning is almost here.
3.
the first or early period of anything; beginning: the morning of life.
Read it for what it says.
That's why Christians knew it wasn't literal days. No sun, no morning. By definition.
The Bible calls whales fish and bats birds.
Actually, not. For example, the word for birds and bats translates to "flying things."
You rationalize day by the sun--and that is the primal conclusion, given Human beings have only known the sun as a source of light and that the sun is a governor ordained by God to reign over the day.
The word "morning" has a meaning, which rules out literal days in Genesis. You can "prove" anything about scripture, if you re-define words to make it work.
But I think we should accept Scripture as it is, not as we'd like it to be.