I've lost track of how many times I've heard such nonsense. People like John Loftus speak of their days as “Christians” just as though being a follower of Jesus has something to do with the depth of theological knowledge or their GPA in Biblical literacy.
It's as though these men and women know nothing of the fact that being a follower of Jesus has to do with inner change, with how you live your life, not by rote learning, but by Spirit driven transformation. It's as though these people have no clue that one can be theologically astute and Biblically literate yet be in a position where they will one day hear Jesus say, “Get away from Me. I never knew you.”
No, as it is said, “If they left us, it was because they were never with us.”