I have a theory that may sound crazy or ridiculous. I believe the "giants in those days" refer to the only thing not mentioned (or understood to be mentioned in the bible. Brace yourselves. We haven't, to my knowledge, found any record of human bones larger than people that may still exist today. 7'6" people still exist today right? The nephillim (how ever it's spelled) would have died in the flood. I believe they were bigger than the giants of post-flood. But we have found giant bones 20-30ft tall. They just weren't human. See my point yet? I believe the "giants in those days" could (as in possibly) were dinosaurs. We assume that the word giant meant that same then that it means now. And I hope you're not looking to find the word dinosaur in the bible. That's what we named them when we found the bones. The original name could have been Nephillim. That's what my common sense or logic would tell me.
I agree that the "giants in those days" part did not refer to the men of old and reknown. I believe the men of old and reknown were offspring of angels and humans. This part of the bible actually supports greek mythology meaning the stories were true. The problem with mythology was the worship of the "sons of God" (angels). God is a jealous god. His servants are not to be worshiped or praised.
And anyone who says that dragons and unicorns did not exist can't believe God's word which refer to both more than once. Not only in fairy tales but also in religion are these creatures mentioned. If the buffalo became extinct and no records could be found, would future generations call them fiction? Probably so. Stop making the bible so difficult. It means literally what it says. The only question is do you believe it or not. The truth is in there, you just have to understand that the language has changed alot in all those years.
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