The conflict between God and Satan is clearly a mismatch in God’s favour in Mark’s Gospel, and the conflict with the authorities, although not without intrigue, lead to a known outcome: the seeming victor of the authorities, Jesus’ crucifixion, is overturned by the victory of God, Jesus’ resurrection. Thus the conflict between the Markan Jesus and the disciples is of the greatest dramatic interest for the implied author and the implied audience. Jesus and the disciples are the only “round” characters in the Markan narrative. The other characters are “flat”: the unclean spirits are always evil; the Pharisees are always conspiring. The disciples change . . . The dynamic portrayal of the disciples in their relation to Jesus is one of the reasons the implied audience is most drawn into their conflict.
Mark's Jesus: Characterisation as Narrative Christology, 2009, p49