Response to: You are attacking a literal interpretation...
It's a common challenge:
You are attacking a literal interpretation of the Bible!
Many times this challenge is thrown out when the argument does not depend on a literal interpretation of the Bible at all -- see, for example, the comments regarding my article Jesus: Unoriginal Moral Thinker. The main thrust of the argument is that Jesus was an unoriginal moral thinker -- and the only thing that could plausibly be considered original is the idea that thought crimes are morally equivalent to real crimes. None of that argument requires a literal interpretation of the Bible.
Other times you are talking to a Christian who draws off the fire of a specific argument by saying something like, "a literal interpretation is silly; the higher approach is to take a nuanced, metaphorical/allegorical interpretation."
This kind of vague talk generally clouds discussion. To avoid this kind of murky no-man's land you should make an effort clarify any ambiguous statements. The following tactic is not to gain an advantage over the person you are talking with -- it's to enhance the flow of ideas in both directions.
Tactic: Make specific claims and ask for specific claims; use clear examples and ask for clear examples.
I aim for the same clarity that I try to draw out of other people. This 'tactic' benefits everyone involved in the discussion. For example, ask: "Do you think that your personal salvation is allegorical/metaphorical or is it literal?"
If he happens to think that his personal salvation is literal, ask, "So do you believe that the physical resurrection of Jesus was metaphorical?"
I haven't met any person who actually thinks that he is going to "literal" heaven because of the "allegorical" physical resurrection of Jesus paid for their "literal sins" -- but it's possible that such people exist.
Keep in mind however you decide to phrase the questions yourself that the point of the conversation should be to determine: What is allegorical, what's metaphorical, what's literal, and how did he decide which was which?
Ask questions with specific examples:
- Noah's flood gets marked under "literary imagination" because it's just plain silly…
- Jesus' being born of a virgin — metaphorical because… well, it's just plain silly…
- Jesus dying and coming back to life again 3 days later… that isn't silly because … ???
How is any miracle in the Bible more or less silly than another?