WEB(i)
19 Then the disciples came to Jesus privately, and said, “Why weren’t we able to cast it out?”
20 He said to them, “Because of your unbelief. For most certainly I tell you, if you have faith as a grain of mustard seed, you will tell this mountain, ‘Move from here to there,’ and it will move; and nothing will be impossible for you.
21 But this kind doesn’t go out except by prayer and fasting.”