Matthew 17:16-21

Thomson(i) 16 I brought him to thy disciples, but they could not cure him. 17 And Jesus answering, said, O faithless and perverse generation! How long shall I be with you"? How long shall I endure you? Bring him hither to me. 18 Then Jesus rebuked the demon and it went out of him, and from that hour the child was cured. 19 Then the disciples came to Jesus in private, and said, Why could not we cast it out? 20 And Jesus said to them, Because of your unbelief. For verily I say to you, If you have faith as a grain of mustard seed, you might say to that mountain, Remove hence to yonder place; and it would remove; and nothing would be impossible to you: 21 but this kind [of power] goeth not forth, unless by prayer and fasting.