Luke 9:40 KJV
And I besought thy disciples to cast him out; and they could not.
Luke 9:40, King James Version
In context
39 And, lo, a spirit taketh him, and he suddenly crieth out; and it teareth him that he foameth again, and bruising him hardly departeth from him.
40 And I besought thy disciples to cast him out; and they could not.
41 And Jesus answering said, O faithless and perverse generation, how long shall I be with you, and suffer you? Bring thy son hither.