So the "ambuguity" lies only in the definition of "unbeliever". Generally when that word is used in the Bible, it refers to someone who doesn't follow Christianity.(Original post by Sithius)
I know they were written by Paul, I slipped up and write to instead of of (see Letters of Paul). Big deal.
Nevertheless, you are missing the point that they aren't inspired by God; therefore your argument is massively problematic. Also, that verse is ambiguous. He isn't explicitly saying that you have to be a Christian, it could just be referring to the belief in God for example.
Are you now going to say Christians who have no problem with homosexuality aren't true Christians, because they don't follow a small reference written by someone who thought it to be wrong (nothing to do with God)? Again, what about the various things which contradict each other on issues throughout the Bible? Surely you must realize that a lot of these contradictions are born out of one man's views, not God's?
Where you draw the line between Christianity and non-Christianity is difficult, and that can be left up to the discretion of the couple. I would say that Christians who honestly believe homosexuality is fine are still Christians, but they're incorrect about something.
Whether or not there are contradictions in the Bible is dubious, and as you say can't have come from God (unless He has an unseen reason to lie, but if that's true, we can't act on it, so that possibility can be discarded). However, no human being can discern what is from God and what isn't, so it's best to treat the Bible as infallible insofar as it's possible.
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