Iron, from what I've read you have a seriously distorted view towards homosexuality in general and I suspect many other things.
There's overwhelming scientific evidence that homosexuality is not a choice, and if you looked at things from a purely logical perspective - if it was a choice, why would about 10% of the Earth's population choose to do something so heavily discriminated against.
Here are the facts, homosexuals are human beings just like you and me, it doesn't matter who they're attracted to, they're living people who are completely equal with the rest of us. So isn't it obvious they deserve equal rights? Denying gay marriage is like denying women the right to vote, or blacks to own land.
I know this isn't going to make any difference to your opinion and a few sentences aren't going to help remedy your warped outlook on life, that's what you'll hopefully do yourself when you grow a pair of balls and think for yourself. Think about what you're doing and why you're doing it, why do you refuse to treat other human beings with the respect they deserve, you're hurting and marginalizing those around you.
I could end this post here, but I know exactly what you'll do. You'll reply with a knee-jerk reaction, never doubting that you could be wrong but rather scrambling for straws that will help to back up your opinion, straws which will inevitably come from your faith-based ideology.
I have nothing against religion, if you believe in a particular faith, then good for you, in this day and age it's going against the grain, so obviously you're capable of some individual thought. Now don't let your religious beliefs impinge on someone else's freedom. One day, when you've wisened up a little you'll regret the discriminatory attitude you've taken.
There's nothing else to say, you need to mature and use your brain to actually think and question what you're doing - till then, you need to realize you're not just having an opinion, you're hurting people.