From the Live Forever book:
pg 96
RESISTING WICKED SPIRIT ATTACKS
17 What should you do if a “voice” from the spirit world speaks to you? What if the “voice” pretends to be a dead relative or a good spirit? Well, what did Jesus do when the “ruler of the demons” spoke to him? (Matthew 9:34) He said: “Go away, Satan!” (Matthew 4:10) You can do that too. Also, you can call on Jehovah for help. Pray out loud and use God’s name. Remember that he is more powerful than are wicked spirits. Follow this wise course. Do not listen to such voices from the spirit world. (Proverbs 18:10; James 4:7) This does not mean that everyone who hears “voices” is being spoken to by demons. At times the hearing of voices can be traced to certain physical or mental illnesses.