the only people in remedial danger where the people who had not yet trusted christ fully (people who had already been saved, but were experiencing the work of the HS in people lives around them, and by association, being blessed themselves)
and the apostle john also made it clear that no one who is truly saved would ever deny christ, as he said, they departed because they were never of us, for if they were of us, they never would have departed.
who are they? Anti Christ.
who is Anti-Christ? one who denys christ.
Yet they were born again because the bible says that all who believe and confess will be saved (circumcision of the heart). Whether they were sincere or not is irrelevant. They trusted and were born again; and then counted the cost and realized it was too much to pay because they really loved the world more than GOD.
Saying a person can be circumcised in the heart and not lost is like saying that a child of Israel could be circumcised in the flesh and not be lost.