Luke

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

And when they were come to the multitude, there came to him a certain man, kneeling down to him, and saying,

And Jesus said unto them, Because of your unbelief: for verily I say unto you, If ye have faith as a grain of mustard seed, ye shall say unto this mountain, Remove hence to yonder place; and it shall remove; and nothing shall be impossible unto you.

And he said unto them, This kind can come forth by nothing, but by prayer and fasting.