13Then the disciples understood that he spake unto them of John the Baptist. 14And when they were come to the multitude, there came to him a certain man, kneeling down to him, and saying, 15Lord, have mercy on my son: for he is lunatick, and sore vexed: for ofttimes he falleth into the fire, and oft into the water. 16And I brought him to thy disciples, and they could not cure him.17Then Jesus answered and said, O faithless and perverse generation, how long shall I be with you? how long shall I suffer you? bring him hither to me. 18And Jesus rebuked the devil; and he departed out of him: and the child was cured from that very hour. 19Then came the disciples to Jesus apart, and said, Why could not we cast him out?