Okay. If we work on the assumption, as I do, that the Bible isn't actually correct, that stance becomes a lot more shaky.
To put this in perspective, saying that gay sex is wrong would be like saying it's wrong to have sex with redheads. A very strange and arbitrary restriction on somebody's choice of sexual partner.
That's without even going into whether or not homosexuality is a choice. I really don't think it is. Put it this way, I'm not attracted to other men. Just can't do it. If that were a choice, I'd be bisexual since I'm pretty good at telling people who dislike my lifestyle to go forth and multiply anyway and there's a thriving gay scene in my nearest city. Bisexuality would suit me just fine.
The reason I'm not bisexual is because I can't simply choose to be.