Did Jesus Tell His Disciples That Some Demons Could Only Be Cast Out By Prayer OR Faith? #212

A desperate father comes to the disciples of Jesus for help. His precious son is tormented by an unclean spirit that seeks to throw him down, and cause him to injure himself. Try as they might, Jesus' disciples cannot heal the boy or cast out the unclean spirit. When Jesus is able to do so with relative ease, the disciples ask Him later the reason for their failure. Mark gives one answer of Jesus, Matthew another. Which is the proper answer: prayer or faith, or is something deeper going on here?