The life of anyone who claims to be a Christian should compared to Scripture to see if it matches up, not the current thinking of the day. That's the standard. Jesus was pretty precise in what characteristics His disciples should display, the major one of which is love. While it is not possible to know the heart of any man, if someone like Hitler claims to be a Christian and does the things that Hitler did, it can be a pretty good bet he wasn't. Talk is cheap. It doesn't mean anything if there's not the life to back it up and true faith will produce that life.
Huh. Is that how it works at your church? Only those whose hearts are comparable to Jesus' heart are considered christians? And you bar the door to anyone who doesn't meet that standard?