The trouble with most Christians is they don't read their bibles and completely ignore what Christ taught.
The REAL trouble with most Christians is that they aren't really Christians.
If you saw a man professing to follow the teachings of the Buddha sitting in Burger King, tapping out a quadruple cheeseburger, you'd say to yourself, "Hmm... I don't think he's really Buddhist." So similarly, if you see a 'Christian' spewing hate and not love, feel free to tell them "you're not really being a follower of Jesus Christ right now. You should fix that one way or the other."
With that said, we're all human. Everyone loses their temper from time to time, and everyone has to wade through the mental and emotional crap in which we were raised. Only the really nutty ones claim to be perfect. The rest of us are just trying to be better than we are right now.