The disciples encounter someone who is attempting to cast out a demonic spirit in Jesus’ name. They try to stop him because he didn’t belong to their little group. Jesus took this opportunity to teach three lessons: 1. We should have a more accepting ecumenical spirit towards other believers. 2. No sin should be so cherished that it keeps us from God. 3. We should avoid actions that could cause a brother or sister in Christ to stumble in their faith.