As another atheist (from a Lutheran background) who has read the bible (it kind of precipitated the whole atheist thing), I totally understand why many Christians believe that the old testament is relevant and believe that their god considers homosexuality to be sinful.

That wasn't what I was taught in my particular brand of Christianity, but having read the book I can totally see where other denominations pick it up. They aren't hallucinating or imagining hateful things in that book, it's all in there, ready to be reinforced or erased and excused, depending on which particular interpretation you take.

I think that reading the bible and coming to the conclusion that the god described in it hates homosexuality (among any number of other things) and that Jesus did not reverse those prejudices is perfectly reasonable. It's also somewhat reasonable (though far less so I think) to take away the idea that the Christian god is genuinely all loving and that Jesus absolved that god of all of it's sins (wasn't he suppose to do that for humanity instead? But it seems like he is most often invoked to absolve the christian god of his sins...).

(That of course isn't to say that I believe the sort of hateful Christianity seen prominently in certain parts of America (and other parts of the world) is acceptable. While I think their interpretation of the Bible is reasonable, I think it is _unreasonable_ for them to believe the Bible is divinely inspired, or that the god they read from those pages is worthy of being worshiped.)