Dr. John Whitcomb joins Brannon for this installment of Ask Dr. John. Question: Is it true that Jews in the Old Testament did not believe in a triune God? I realize they do not accept Jesus as the Messiah, but think they still await their Messiah. Question: I have studied all of your Bible charts on Old Testament chronology. What motivated you to study and prepare these charts? Question: Can you please explain Matt. 24:13? Does this verse have anything to do with the doctrine of the perseverance of the saints? Question: Are believers currently in heaven who are yet to receive their resurrected bodies capable of recognizing one another (see 2 Cor. 5:1-8)? Question: When will the resurrection of Old Testament saints take place? Question: Will believers be filled with the Spirit in heaven? Question: Do demons automatically leave a person who becomes a Christian? Do demons cause diseases, such as cancer? Question: Many people are making resolutions at this time of the year. Is this Biblical? How can we do so in a way that will be spiritually successful? Question: I am always blessed by your answers to Bible questions and would like to study the Bible to know it more completely myself. Can you give me some practical advice? Question: What are some of the greatest challenges facing missionaries today? Topic: We take your questions by phone.