5. The Doctrine Nazi – This is a rarer species, but dangerous nonetheless. He took one seminary class and has read too many blogs, and now he’s the expert at everything. Learn to avoid him, for a simple “hello” can turn into a twenty-minute diatribe on the finer points of Calvinism. He is the self-proclaimed theology police of your church and patrols the halls listening for errant or uninformed beliefs to quash.