Honestly, Flirb, now you're being difficult. How do you define a Christian at all then, or hell, ANYONE? Can I go around saying I'm an atheist while telling people to believe in God? You might not believe it, but there's more that defines being a Christian (or a member of any belief system) than just saying "I believe in God!" And I'm not even talking about whether you're a good practitioner of said religion, I'm talking about just various beliefs and practices you claim to follow. I don't think you'd consider me a Muslim, for instance, if I went around saying "I'm a Muslim! Also, I don't believe Muhammad was the one true final prophet of God!"
Also, while there's certainly debate over points of how to be an ideal Christian, to say the matter is entirely subjective is to say the same of being a good German, or a good Democrat, or even a good scientist: they all belong to social groups which are defined by expected behavior, whether it be service to one's country, to one's political ideologies, or one's method of examining evidence. Hell, even good artists aren't completely subjective to define: technical skill, ability to evoke emotion, communicating a message. According to you, you're as much a Christian as I am (and apparently that's the worst insult I could give you </sarcasm>).
Yes to the first two, given my previous hypotheticals. As soon as people are proven the existence of God, they will automatically depend on God to do everything for them (see: every superhero dilemma), which is a problem I think plagues most believers. To your third, I don't believe that to be the case and is more the common belief pushed by the false vocal majority.
Perhaps not for you, but for most I talk to, it's because they were surrounded by people who called themselves Christian and acted against the teachings of Christ and said "I don't want to be anything like these horrible people!"
I'd also like to point out that Christianity does not have the monopoly on hypocrites -- that would be the human race.
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