9. And as they were descending from the mountain, Jesus instructed them, saying, "Tell no one about the vision, until the Son of man has risen from the dead."
10. And his disciples questioned him, saying, "Why then do the scribes say that it is necessary for Elijah to arrive first?"
11. But in response, he said to them: "Elijah, indeed, shall arrive and restore all things.
12. But I say to you, that Elijah has already arrived, and they did not recognize him, but they did whatever they wanted to him. So also shall the Son of man suffer from them."
13. Then the disciples understood that he had spoken to them about John the Baptist.
14. And when he had arrived at the multitude, a man approached him, falling to his knees before him, saying: "Lord, take pity on my son, for he is an epileptic, and he suffers harm. For he frequently falls into fire, and often also into water.
15. And I brought him to your disciples, but they were not able to cure him."
16. Then Jesus responded by saying: "What an unbelieving and perverse generation! How long shall I be with you? How long shall I endure you? Bring him here to me."
17. And Jesus rebuked him, and the demon went out of him, and the boy was cured from that hour.
18. Then the disciples approached Jesus privately and said, "Why were we unable to cast him out?"
19. Jesus said to them: "Because of your unbelief. Amen I say to you, certainly, if you will have faith like a grain of mustard seed, you will say to this mountain, 'Move from here to there,' and it shall move. And nothing will be impossible for you.
20. But this kind is not cast out, except through prayer and fasting."