Luke 9:36-41
English Standard Version
37On the next day, when they had come down from the mountain, a great crowd met him.
38And behold, a man from the crowd cried out, "Teacher, I beg you to look at my son, for he is my only child.
39And behold, a spirit seizes him, and he suddenly cries out. It convulses him so that he foams at the mouth, and shatters him, and will hardly leave him.
40And I begged your disciples to cast it out, but they could not."
41Jesus answered, "O faithless and twisted generation, how long am I to be with you and bear with you? Bring your son here."