It is not to the person possessed but to the evil spirit within him that we must speak. Deliverance must be ministered in the name of the Lord. It is the name of Jesus that gives us power and authority. The name itself, however, is not to be used lightly or experimentally. The consequences for doing so may be disastrous.
Faith is absolutely essential in ministering deliverance.
Through the laying on of hands. By special miracles of God. By a word. By the anointing upon prophetic music. But we don't have to listen to the demons or put up with the trouble and commotion they may try to cause during the process of exorcism.