A while ago I was talking with two of my friends, and one mentioned that her boyfriend thinks being gay is a choice. They didn't know I was, so I told them, said I didn't choose. And the other one told me straight up that the Bible says it's wrong. This same friend also told me later, when I was complaining about a professor's comment that we didn't come from apes (that it was irrelevant to the discussion, not whether I agreed with the statement), that she believes in literal six-day creation. I am a Christian, but one, the Levitical law doesn't apply to us,, and two, how can anyone with a brain honestly believe the earth is only a few thousand years old?
From what I understand of Christianity's view of Jesus, he replaced Jewish laws in the OT, which is why Christians don't feel they have to keep kosher and other Leviticus laws. But the first thing the fundies appeal to when they claim homosexuality is a sin is Leviticus, which is frankly quite baffling.
When the Romans invaded the "Holy" land, the first thing they did was to exterminate the lawmakers. These guys adjusted the laws to conform with the times, but the Romans made sure that only Roman law was obeyed (JC was put up at the 3 Nails Hotel in accordance with Roman Law, but the Jews got the blame) When the Romans finally left, Judiasm was then run by the Rabbis who refused to change any law, and have done so for the last 2 millenia.