However, there is a great difference between making a judgement about whether of not someone is a cop and has a warrant, and whether or not someone is actually a Christian...the steps one would take to verify that the cop is actually doing his required duty, according to the law, and my getting my attorney to my house, are all pretty straightforward things...not really subject to interpretation...
However, when trying to determine if one is a Christian, much of that comes down to ones own personal interpretation of the Bible...and there is the problem...no one on this earth, not one single person, not me, not you, has the market on what the truth of every single passage in the Bible means, or on what every single word means...so much of it comes down to personal interpretation....its not as straightforward as your propose it is...
It is as straightforward as I propose. Many make hay about interpretations of the Bible. But it isn't interpretation.
People argue interpretation so that they may hide behind false constructs. When John Grisham tells us in the Partner that the woman in the end took the money and disappeared, we don't need to interpret that to know what he's saying. We need to read and understand the language in it's context. And that is the problem, not people's reading skills; but, their willingness to apply them in the face of people telling them that they are too 'stupid' or 'unlearned' to understand written language. If they convince you that you're too dumb and that you need them, they can tell you anything they want and you've subjected yourself to willfull ignorance rather than using your own capable capacities.
No, it isn't about interpretation. Scripture tells us plainly in numerous places all the marks which define followers of Christ. The terms are unambiguous and specific. And anyone can look at them and tell by their own
capacities whether the claim fits what they are following or whether it fits scripture or both - or neither. It is not beyond your capacity to know.