"The Bible says 'X'...I grew up believing the Bible, so I believe 'X', and no one can show me any 'proof' that 'X' is false, so my belief is as valid as your science.."
That's it in a nutshell. But the belief is not as valid as the science. That's the whole point. It's self-evidently not so. I believe in the science (without accepting it as truth) because science searches for and presents me with evidence. Growing up being made to believe in the Bible instructs you to stop looking for evidence. And no, I won't turn the bloody record over. It's the whole nub of the thing.