Mark 9:17-19

Revised Standard Version

¹⁷ And one of the crowd answered him, “Teacher, I brought my son to you, for he has a dumb spirit; ¹⁸ and wherever it seizes him, it dashes him down; and he foams and grinds his teeth and becomes rigid; and I asked your disciples to cast it out, and they were not able.” ¹⁹ And 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.”