12. Christianity is a moving target.
The Bible never explicitly states what Christianity is, and no two Christians will agree 100% on every aspect of Christianity. I can't say, "This belief of Christianity is illogical and absurd," because some Christian out there will say, "That's not what true Christians believe." If I say, "A lot of Christians believe it." They can say, "Well, they're not true Christians."
Every Christian has to use the No True Scotsman argument eventually, because there are no true Christians. There’s just a bunch of people projecting their own cultural values into a foreign, obsolete book they’ll never understand.
When you go into a debate with a Christian you have no idea how they define Christianity. So you have no idea what they’ll claim or dismiss. It doesn’t matter how accepted the beliefs you’re arguing against are, if you say Christianity is anything other than exactly what they believe it is, then they’ll shoot you down for not understanding what Christianity really is. So fighting Christianity is like fighting a shape shifting ghost with multiple personality disorders that is in denial.
13. If all else fails, you're going to hell and/or you're a fool.
Psalm 14:1 states, "The fool has said in his heart there is no God."
1 Corinthians 2:14 states, "The person without the Spirit does not accept the things that come from the Spirit of God but considers them foolishness and cannot understand them because they are discerned only through the Spirit." or
1 Corinthians 3:19 states "For the wisdom of this world is foolishness before God."
If you're a non-Christian, it doesn't matter how knowledgeable you are about textual or historical context in the Bible. Your point of view is invalid, because why would a Christian listen to a Hell-bound servant of Satan? By Biblical standards, they shouldn't. The Bible says to have faith and put Satan behind them.
It's circular logic to say that any criticism of the Bible is foolish because the Bible says that any criticisms of the Bible are foolish. Not only that, but these passages teach Christians that losing an argument proves you're right. That's logic-proof. It's impossible to debate someone, if the premise of their argument is that you and all your evidence are automatically invalid.
14. Faith and reason are apples and oranges.
Back a Christian into a corner with enough facts and logic and they'll eventually resort to side stepping reality by saying that faith/religion fills a void that logic/science can't. The idea is that logic and science can only take you so far in understanding this giant, bizarre universe we've all found ourselves stranded in; and when those tools fail, faith/religion pick up the trail and fill in the gaps. Therefore, you can not and should not tread on the domain of religion because it's exempt from logical criticisms.
On it's own, this argument sounds nice. It ties up the universe in a pretty package with a nice bow on top. In reality this argument is meaningless. Remember that religion is merely an expression of a primitive society's cultural values. So faith in religion is not a transcendental experience. It's just refusing to think about what you've been told. Frankly, that's just dumb. Choosing faith over logic is ultimately just choosing ignorance over awareness.
So yes, faith and logic are separate languages, but faith is the language of insanity, and logic is the language of sanity. Since I don't have the psychiatric training to communicate effectively with people who demonize sanity, I find it very hard to debate Christians about the difference between their antiquated delusions and scientific reality.
15. What would we argue about anyway?
Christianity is mythology, and every single page of the Bible contains evidence to support this conclusion. Debating individual passages in the Bible is like debating individual passages in Mein Kampf. Even Hitler was right about a few things. That doesn't mean I'm joining the Third Reich. (Fun fact, do you know what the First Reich was? The Holy Roman Empire.)
The only debate I could possibly have with a Christian would be me trying to convince them that they've accidentally based their life on an embarrassing mythology while my Christian opponent would try to convince me to ignore all the glaring evidence in the Bible that reveals it as a primitive culture's mythology. Well, I'm not going to abandon reason, and Christians aren't going to abandon their faith over the course of a debate. So we really don't have much to discuss anyway.
16. Why would I argue about something you don't believe in anyway?
As pointed out in reason #10, every self-proclaimed Christian believes Christianity is something different. But if we can't agree on anything else about Christianity, I have to assume that being a Christian means being Christ-like. Being a Christian means asking yourself, "What would Jesus do?" and then actually doing what Jesus would do.
This raises the question, what did Jesus do? Jesus gave away everything he owned and devoted his life to helping people in need and publicly advocating forgiveness, acceptance and love. By that definition, I've never met a single Christian in my entire life. Not even close.
All the Christians I've met make up for their lack of walking the walk, by talking louder and meaner. If you're not going to walk the walk, then I don't want to hear you talk the talk. Don't you dare tell me I need to devote my life to a cause you won't even devote yours too. Even without living like Christ, Christians don't even believe in the Bible.
As pointed out in reason #10, before I can have a discussion with a Christian, I have to establish all the passages you've dismissed as being metaphors or obsolete until the only teachings in the Bible left for you to follow are the ones that coincide with your modern cultural values, and we already share most of those. Don't tell me to take a step backwards when you're already an apostate yourself.