Mark 9:28-30

Young's Literal Translation

²⁸ And he having come into the house, his disciples were questioning him by himself -- `Why were we not able to cast it forth?'

²⁹ And he said to them, `This kind is able to come forth with nothing except with prayer and fasting.'

³⁰ And having gone forth thence, they were passing through Galilee, and he did not wish that any may know,