Mark 9:17-18

A man spoke up out of the crowd. “Teacher,” he said, “I have a son possessed by a demon that makes him mute. I brought him here to you, Jesus. Whenever the demon takes control of him, it knocks him down, and he foams at the mouth and gnashes his teeth, and his body becomes stiff as a board. I brought him to your disciples, hoping they could deliver him, but they were not able to do it.”