according to Jesus your actions show if you are true or false. but according to many Christians today its what doctrines you believe which is very confusing being as so many churches have so many different doctrines.
i tend to go with what Jesus said, its tried and tested being as there is no grey area, you either do good works or you dont. theology and doctrines however are nothing but grey areas and can be argues till the cows come home. some have been debated for almost two thousand years.
Jim Jones is a good example, was an expert on scripture, taught things like blacks and whites should be able to worship together, all sounds good but these were just words he said in front of people, his actions show that he was a drug addict, adulterer, homosexual, and in the end a mass murderer.