Mark 9:14-18

When they came to the other disciples, they saw a large crowd around them and the teachers of the law arguing with them. As soon as all the people saw Jesus, they were overwhelmed with wonder and ran to greet him. ‘What are you arguing with them about?’ he asked. A man in the crowd answered, ‘Teacher, I brought you my son, who is possessed by a spirit that has robbed him of speech. Whenever it seizes him, it throws him to the ground. He foams at the mouth, gnashes his teeth and becomes rigid. I asked your disciples to drive out the spirit, but they could not.’