Don't you love how some Christians think they can authoritatively judge who is and who isn't a Christian?

Right we have to be careful not to get caught up in that trap of the enemy of judging Christians because they have some sin in their life - because everyone sins whether they want to or not. Actually I had "judging-others" problems myself and God taught me to be more loving by knowing that I am a sinner and to recognize that I am constantly missing the mark and need the grace of Jesus always.