Christians do not give any more of a shit about what the Bible actually says than any atheist. Finding this or that Bible quote that could be seen to support what they're saying is just a way for the religious person to ascribe divine origin to their assertions. Psychologically it is a way for them to defer the source of the assertion to a god, which has the benefit of elevating the authority of the [supposed] claimant to that of a supreme and holy source which couldn't possibly be wrong (after all, he makes all the rules.) In their mind it removes the responsibility of supporting their claims -- now you're arguing with god and in order to do that, you have to disprove the whole religion. But that's a ridiculous task and attempting to do it will just make you look like some kind of close minded bigot trying to force your beliefs down everyone's throat.
This is why quoting the Bible is of no use. He already knows what it says, it says everything he's saying and you have to kill god in order to prove otherwise. Really the supposition that any given belief is a "religious" belief is an inherently dishonest rhetorical strategy.