And my Lord standing in the midst of the cave and enlightening it, said: John, unto the multitude below in Jerusalem I am being crucified and pierced with lances and reeds, and gall and vinegar is given me to drink. But unto thee I speak, and what I speak hear thou. I put it into thy mind to come up into this mountain, that thou mightest hear those things which it behoveth a disciple to learn from his teacher and a man from his God
http://gnosis.org/library/actjohn.htm
...and the Markan episode about the Independent Exorcist:
38 “Teacher,” said John, “we saw someone driving out demons in your name and we told him to stop, because he was not one of us.”
39 “Do not stop him,” Jesus said. “For no one who does a miracle in my name can in the next moment say anything bad about me, 40 for whoever is not against us is for us. 41 Truly I tell you, anyone who gives you a cup of water in my name because you belong to the Messiah will certainly not lose their reward.
39 “Do not stop him,” Jesus said. “For no one who does a miracle in my name can in the next moment say anything bad about me, 40 for whoever is not against us is for us. 41 Truly I tell you, anyone who gives you a cup of water in my name because you belong to the Messiah will certainly not lose their reward.
In both the cases a revelation is given to John.
In both the cases, the problem is there out about an independent fact (respectively an exorcism and a crucifixion).
In both the cases Jesus secures John that the independent fact will have a positive end, in the general scheme of providence.
Now, the differences:
Mark is polemical against John: pace John, the exorcism by the Independent Exorcist has the Jesus's confirmation about the his being a true exorcism by Jesus himself.
Acts of John is supporting John: the crucifixion in act is only a way to deceive the people around. It is a false crucifixion of the Son.
So is "Mark" correcting a previous source about John of Zebedee, to make it anti-John ? Or vice versa?