Mark 9:25-29

25 When Jesus saw that the people came running together, He rebuked the unclean spirit, saying to it, "Deaf and dumb spirit, I command you, come out of him and enter him no more!" 26 Then the spirit cried out, convulsed him greatly, and came out of him. And he became as one dead, so that many said, "He is dead." 27 But Jesus took him by the hand and lifted him up, and he arose. 28 And when He had come into the house, His disciples asked Him privately, "Why could we not cast it out?" 29 So He said to them, "This kind can come out by nothing but prayer and fasting."