There are so many Christians out there who want to say, "I am a Christian, but I do believe in science. There is a lot of compelling evidence for evolution, but I am going to have to say that being gay is wrong because the Bible says so." Those are also the ones that say "Well, some of the stories in the Bible aren't meant to be taken literally. There was no way Noah and his sons and daughters repopulated the earth, but the part of the Bible that talks about God coming back one day; that's going to happen and you need to be ready."
The Bible isn't a "Choose Your Own Adventure" book. At least, the one that I read growing up didn't say "If you want to go to heaven, turn to page 379," or "If you want to sit in the belly of a whale, turn to page 168." You can't just throw out the parts that you don't like or that you feel are outdated and just follow the parts that are warm and cuddly.
I detest when Christians enter into an debate with atheists and, when we call them out on a certain part of the Bible, say "Well, that part isn't meant to be followed anymore, or that was just a story, not something that really happened." I say they either need to own the Bible -- the whole thing -- as true, or denounce it as a fairy tale, but stop picking and choosing which parts of it fit their lives today.