This is a tricky one for believers and we all know it. However, being realistic about it, if knowledge had been provided to man a few thousand years ago that the earth was billions of years old, he wouldn't have known what to do with it.
As a believer myself, I have to be honest that I do not think the earth is only 6000 years old at all. I do think humans as we are now might be though.
There are clues in the Scriptures along the lines of one day for God is like a thousand years for man.
This comes a lot closer to the truth, I believe, but again you have to be reasonable in this situation. Man, a few thousand years ago, was incapable of assimilating that type of information - it was simply beyond his understanding or powers of reasoning. Hypothetical scenario - Had they been given a fully functioning computer they would either have sat on it as a chair or maybe even worshipped the monitor in the same way kids have done with TV screens for decades:)
So what we have, I feel, is a sort of compromise. God, being the Author of Life and the greatest of any or all who have understanding, would have been fully aware of the implications of telling BC man too much information. I don't need to elucidate, it should be obvious to anyone with a decent sort of understanding.
God allows people to believe whatsoever He chooses. It is His supreme right as it is also His divine right, as The Creator, to exercise His Will whensoever He chooses to, i.e. to intervene or not to in any and every situation.
So the most likely is that God told at least one contributor to the Scriptures that for Him, one day was more like a thousand years whilst actually knowing, of course, that the real figure was significantly higher say ~ 2-5 billion years. That figure would have meant absolutely nothing to any individual alive at that time. God would not waste His time revealing truth to people incapable of understanding it. Isn't that obvious?
I am hoping that people understand what I am saying here as it really is that plainly obvious.
As I have said, the most remarkable thing of all and the one point above all others that people miss, is that at some point, those who wrote the Scriptures were made aware that the universe and the earth were formed by processes and also, maybe more crucially, even man himself.
The clues are all there in the Scriptures, you just need to be like a child to understand..... why?
Because a young child is much more likely to listen to their parent.
When people get older they tend to get a bit ..... you know ..... sort of .... smart***.
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