In the story about Jesus healing a boy suffering from an “unclean spirit,” we see what appears to be Jesus rejecting debate, questioning, and intellectual disputation. According to the Oxford Annotated Bible, Jesus’ statement that potent faith comes from “prayer and fasting” is to be contrasted with the argumentative attitude on display in verse 14. This places religious behavior like prayer and fasting well above intellectual behavior like philosophizing and debating. The reference to “prayer and fasting,” by the way, is limited almost entirely to the King James Version — nearly every other translation just has “prayer.”
Some Christians have argued that the disciples’ failure to heal the boy was partly due to the fact that they debated the matter with others rather than simply giving themselves entirely over to faith and acting on that basis. Imagine if doctors today were to behave in a similar manner.
These problems only matter if we insist on reading the story literally. If we treat this as an actual healing of an actual person suffering from a physical ailment, then neither Jesus nor God comes away looking very good. If it is just a legend that's supposed to be about spiritual ailments, things look different.
Arguably, the tale here is supposed to help people understand that when they are suffering spiritually, then sufficient faith in God (attained through things like prayer and fasting) can relieve their suffering and bring them peace. This would have been important for Mark’s own community. If they continue in their unbelief, however, then they will continue to suffer — and it isn’t just their own unbelief which is important. If they are in a community of unbelievers, then that will impact others because it will be more difficult for them to hold on to their faith as well.
