Questions From Readers
According to Matthew 17:20, the apostles were unable to cure an afflicted boy ‘because of their little faith.’ At Mark 9:29, however, their inability is linked to a need for prayer. Why are different reasons given in different Gospel accounts?
Actually, the two accounts are supplemental, not in conflict. First, look at Matthew 17:14-20. A man reported that his son was an epileptic and that Jesus’ disciples could not cure the lad. Jesus then cured the boy by expelling a demon who was afflicting him. The disciples asked why they could not expel the demon. According to Matthew’s account, Jesus replied: “Because of your little faith. For truly I say to you, If you have faith the size of a mustard grain, you will say to this mountain, ‘Transfer from here to there,’ and it will transfer, and nothing will be impossible for you.”
Now turn to Mark 9:14-29, where we find more details. For example, Mark 9:17 supplies the detail that in this case the epileptic-type seizures were caused by an evil spirit. It is worth noting that the Bible says elsewhere that Jesus cured epileptic and demonized people. (Matthew 4:24) In this unique situation, the seizures were caused by a “speechless and deaf spirit,” that is, a wicked spirit, which physician Luke confirms. (Luke 9:39; Colossians 4:14) Note at Mark 9:18 the phrase, “Wherever it [the demon] seizes him.” So the boy was not continuously harassed by the demon, only occasionally. Still, the disciples could not expel the demon and thus cure the lad. When they asked why, Jesus replied: “This kind cannot get out by anything except by prayer.”
A careful reading of Mark’s account, though, shows that there is no conflict with what Matthew recorded. At Mark 9:19, we read that Jesus bemoaned the faithlessness of that generation. And in Mr 9 verse 23, it is recorded that he told the boy’s father: “All things can be to one if one has faith.” So Mark too stresses the importance of faith. It is just that in Mr 9 verse 29, Mark provides an additional detail. Mark adds what Jesus said about prayer, which neither Matthew nor Luke included.
What, then, can we say? On other occasions both the 12 apostles and the 70 disciples cast out wicked spirits. (Mark 3:15; 6:13; Luke 10:17) But in this instance the disciples could not expel the demon. Why? If we combine the details mentioned in the various accounts, we must conclude that they were not prepared to do so in this case. Perhaps part of the problem was the sort of demon involved, since it seems that demons may have differing personalities, interests, and even abilities. With this one, particularly strong faith and fervent prayer for God’s help were needed. Of course, Jesus had such faith. He also had the backing of the Hearer of prayer, his Father. (Psalm 65:2) Not only could Jesus heal the afflicted boy by casting out the demon but he did so.