Mark 9:17-22

17And someone from the crowd answered him, "Teacher, I brought my son to you, for he has a spirit that makes him mute.

18And whenever it seizes him, it throws him down, and he foams and grinds his teeth and becomes rigid. So I asked your disciples to cast it out, and they were not able."

19And he answered them, "O faithless generation, how long am I to be with you? How long am I to bear with you? Bring him to me."

20And they brought the boy to him. And when the spirit saw him, immediately it convulsed the boy, and he fell on the ground and rolled about, foaming at the mouth.

21And Jesus asked his father, "How long has this been happening to him?" And he said, "From childhood.

22And it has often cast him into fire and into water, to destroy him. But if you can do anything, have compassion on us and help us."