What about Leviticus, then, you 'phobe?

One of the best pieces I've encountered on dealing with an advocate of homosexual practice who accuses one of being some sort of mental defective: yep, by Greg Koukl. It's at the 28 minute mark (and, mind you, I disagree with his Calvinistic aspects, just for the record).

I'd tackle it a little differently at the start:

The questioner challenges you about Leviticus 20:13 as the basis of Christian 'homophobia'.

I respond: 'are you an ancient Jew?'...answer is 'no', I continue 'you've nothing to worry about then, so what's the problem?'

Some response...then 'I'd be more concerned about Paul the Christian messenger's letter to his friends in Rome (Romans 1:18-32)'

Then pick up Koukl's response.

Now, remember, this is only if the issue comes up in this context. Our job is not to judge individuals, it's to make disciples. I Cor 5:9-13 applies.

The rebuttal of the use of Leviticus is strategically there to open a discussion of what the Bible is (the collection of God's interactions with his people through history to prepare the way for Messiah) and is not (a collection of ahistorical and disconnected aphorisic instructions about behaviour...which the Koran is).