--> Funny thing is, considering what you ask me....is that I think the 'days' in Genesis 1 were actual days (of the ordinary 24 hour variety). !
Funny, eh? People often don't quite get what each other are saying. That's the normal discussion.
But....If in contrast another person takes the word "day" in Genesis 1 as meaning a longer time period -- not a 24 hour day, but something else, like a
"day" in just the next chapter, Genesis 2, which isn't merely a 24 hour day obviously.... (verses 4 and 17 in Genesis 2, in many translations) well, that's ok too.
I'm content to merely say "ah" (about their view that a "day" in Genesis 1 is longer than 24 hours, because this clearly, clearly is *not* something to argue over ever in any way that is 'contentiousness' (which we are instructed not to do anyway).
I don't even need to say anything more past my friendly "ah". I may tell them my view if they seem interested, but....well, most people don't even want to hear what other people think way too often, because they themselves don't feel listened to. They have a driving need -- to be heard. If I can, I want to follow the golden rule, and make them feel heard. To the extent I'm able.
The only 2 reasons to be concerned are if they either A) are making out their interpretation of this non-gospel thing as if their particular interpretation *must* be believed as if it were the gospel (!), and then I want to talk to them about Matthew 7: 24-27, the only chance they have to endure and make it. The only thing that *does* save -- real faith in Christ and following Him. So that they can see *that* is the only saving belief, and the others are not saving.
Or (harder to guess)-- B) If they appear to have "built their house" partly or significantly on "sand", any and everything other than the "rock" of hearing and doing as Christ said. Then it's to tell them about the rock, before the inevitable storms of life hit their house.
Now, maybe they are on the rock, and they
aren't in any way making their interpretation of Genesis 1 to be gospel. They're
not saying that anyone who has a different interpretation "doesn't believe in God" or other big warning signs that would suggest they themself have based their faith on sand.
Our theories are merely theories. Here's the known: God created all that is, and that means all, including galaxies, nature, physics, all.