At one point, the disciples of Jesus witness someone using his name to cast out demons. This troubled them. Here's Mark 9:38-39:
The implication seems to be that this man was not (yet?) a true believer, but was successfully performing exorcisms nonetheless. And yet, we are later told that such exorcisms are in fact a sign of true believers. This is Mark 16:17-18:
So, is casting out demons a sign of a true believer, or not?
This problem doesn't strike me as difficult. Firstly, the verse in Mark 16:17 is part of the "Longer Ending of Mark", which is regarded by many scholars as suspect, and probably not part of the original gospel.
But even if we put that aside, is there really a contradiction? I think not. Jesus himself seems to imply that the man performing exorcisms was well on his way to becoming a genuine believer. Furthermore, the later passage gives a list of signs that will accompany true believers, but doesn't explicitly rule out the possibility that some non-believers could do some of the same things.
Admittedly, this might seem to defeat the point of the list: to tell us how to recognise believers. However, a number of skilled people can pick up dangerous snakes safely. Does the verse imply that - unless they're Christians - they shouldn't be able to? I don't think so; it only says that (some) true believers will also perform such feats.
Anyway, none of this is relevant if the Longer Ending is not the original ending.
Updated: 2008-06-13
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