Template:Jehovah's Witnesses Edmund Charles Gruss (c. 1933) is Professor Emeritus at The Master's College in Santa Clarita, California and an author. He researches groups he considers to be "cults" and the occult and has written many books on those subjects especially on the Ouija Board and Jehovah's Witnesses.
Gruss was a member of the Jehovah's Witnesses from the age of seven to seventeen. He subsequently converted to evangelical Christianity after he "found Christ."
- The Jehovah’s Witnesses and Prophetic Speculation, 1972
- What About the Ouija Board?, 1973
- We Left Jehovah's Witnesses: Personal Testimonies, 1974
- The Ouija Board: Doorway to the Occult, 1975, 1994
- Apostles of Denial: An Examination and Exposé of the History, Doctrines, and Claims of the Jehovah’s Witnesses, 1975
- What Every Mormon Should Know, 1976
- The Ouija Board, 1986
- Cults and the Occult, 1994
- The Jehovah’s Witnesses: Their Claims, Doctrinal Changes, and Prophetic Speculation, 2001
- The Four Presidents of the Watch Tower Society: Jehovah's Witnesses, 2003
- What Every Mormon (and Non-Mormon) Should Know, 2006