Thomas Witzig is a physician at the Mayo Clinic in Rochester, MN. He has a clinical and research practice in the area of cancer, specifically lymphoma. He became a Christian at age 18 and has been a follower of Jesus ever since. He is married to Diane Gramm who is a nurse educator and also a Christ-follower. They have two grown children and one grandchild. Dr. Witzig writes this topical study guide using a question format with answers coming straight from the Bible. His background in medicine becomes apparent in the short application sections that accompany the topics.