Mark 9:16

13 But I say unto you, that Elijah is come, and they have also done unto him whatsoever they would, even as it is written of him.

14 And when they came to the disciples, they saw a great multitude about them, and scribes questioning with them.

15 And straightway all the multitude, when they saw him, were greatly amazed, and running to him saluted him.

16 And he asked them, What question ye with them?

17 And one of the multitude answered him, Teacher, I brought unto thee my son, who hath a dumb spirit;

18 and wheresoever it taketh him, it dasheth him down: and he foameth, and grindeth his teeth, and pineth away: and I spake to thy disciples that they should cast it out; and they were not able.

19 And he answereth them and saith, O faithless generation, how long shall I be with you? how long shall I bear with you? bring him unto me.