Mark 9:25-29

When Jesus saw that a crowd was quickly gathering, he rebuked the unclean spirit, saying to it, “You mute and deaf spirit, I command you: Come out of him and never enter him again.” Then it came out, shrieking and throwing him into terrible convulsions. The boy became like a corpse, so that many said, “He’s dead.” But Jesus, taking him by the hand, raised him, and he stood up. After he had gone into the house, his disciples asked him privately, “Why couldn’t we drive it out?” And he told them, “This kind can come out by nothing but prayer.”