“Then the disciples came to Jesus privately and said, ‘Why could we not cast it out?’ So, Jesus said to them, ‘Because of your unbelief; for assuredly, I say to you, if you have faith as a mustard seed, you will say to this mountain, ‘Move from here to there,’ and it will move; and nothing will be impossible for you. However, this kind does not go out except by prayer and fasting.’” (Matthew 17:19–21, NKJV)

While Jesus, Peter, James and John were up on the mountain, the other apostles where in the valley below. A father brought his son to them who was possessed by a demon that made him mute and often caused him to fall into the fire or water. The apostles tried to cast out the demon, but they could not do it. No doubt their failure greatly troubled them. They went to Jesus privately and asked Him, “Why couldn’t we cast it out?" Jesus replied that it was because of their little faith.

Now I think this shocked them. Hadn’t they believed in Jesus and followed Him everywhere? Hadn’t they cast out demons before when Jesus sent them out to preach in the towns of Israel? What went wrong this time?

Faith is a mystery. It is a gift, but it is also something we must exercise. If the disciples had nothing to do with it, then why would Jesus speak to them so often about their little faith? (Matthew 6:30; 8:26; 14:31; 16:8) If we can truly move mountains with only a mustard seed of faith, then how much faith do we really have? The mountain before them was this demon who had control of the boy, and they could not move it because of their unbelief. In addition, this kind of demon would not go out except by prayer and fasting. From this we conclude that the combination of faith, prayer, and fasting is the strongest weapon we have in our arsenal against Satan.

Are there any mountains that need moving? Are there spiritual strongholds in your life or in the lives of others that must be torn down? Are there blinders over people’s eyes that must be lifted? It only takes a mustard seed of faith to start the process. But some mountains also require prayer and fasting. Are you willing to sacrifice to set people free from the devil’s grip? How desperate are you to move that mountain?