When you use circular definitions, as you're doing now, you can re-define a word to be whatever is convenient to you. If Christianity is also defined by what Christians do, then what defines a Christian? You have to ground it in a concrete definition at some point, and that definition is: the teachings of Christ. If a Christian acts in a way that is against the teachings of Christ, then that is not Christian behavior, and is not representative of Christianity. That's a pretty simple and unambiguous concept.
Your "No True Scotsman" variant just shows that you don't really grasp this idea. Ironically, what you're doing by making Christianity a grab-bag of bad behavior from people you don't like, instead of grounding it in a clear and unambiguous definition, is a clever perversion of this fallacy.
Your "No True Scotsman" variant just shows that you don't really grasp this idea. Ironically, what you're doing by making Christianity a grab-bag of bad behavior from people you don't like, instead of grounding it in a clear and unambiguous definition, is a clever perversion of this fallacy.