17 Someone from the crowd answered him, “Teacher, I have brought to you my son possessed by a mute spirit.
18 Wherever it seizes him, it throws him down; he foams at the mouth, grinds his teeth, and becomes rigid. I asked your disciples to drive it out, but they were unable to do so.”
19 He said to them in reply, “O faithless generation, how long will I be with you? How long will I endure you? Bring him to me.”
20 They brought the boy to him. And when he saw him, the spirit immediately threw the boy into convulsions. As he fell to the ground, he began to roll around and foam at the mouth.
21 Then he questioned his father, “How long has this been happening to him?” He replied, “Since childhood.
22 It has often thrown him into fire and into water to kill him. But if you can do anything, have compassion on us and help us.”
23 Jesus said to him, “‘If you can!’ Everything is possible to one who has faith.”