Matthew 17:14-21

When they came to the crowd, a man came to Him and knelt before Him, saying, “Lord, have mercy on my son, for he is an epileptic and suffers terribly. He often falls into the fire and often into the water. I brought him to Your disciples, but they could not heal him.” Then Jesus answered, “O faithless and perverse generation, how long shall I be with you? How long shall I bear with you? Bring him here to Me.” Jesus rebuked the demon, and he came out of him. And the child was healed instantly. Then the disciples came to Jesus privately and said, “Why could we not cast him out?” Jesus said to them, “Because of your unbelief. For truly I say to you, if you have faith as a grain of mustard seed, you will say to this mountain, ‘Move from here to there,’ and it will move. And nothing will be impossible for you. But this kind does not go out except by prayer and fasting.”