Mark 9:27

25When Jesus saw that a multitude came running together, he rebuked the unclean spirit, saying to him, “You mute and deaf spirit, I command you, come out of him, and never enter him again!”

26After crying out and convulsing him greatly, it came out of him. The boy became like one dead, so much that most of them said, “He is dead.”

27But Jesus took him by the hand and raised him up; and he arose.

28When he had come into the house, his disciples asked him privately, “Why couldn’t we cast it out?”

29He said to them, “This kind can come out by nothing but by prayer and fasting.”