The mystery of the Key of David, in Rev 3:7, has been hiding in plain sight for several thousand years. People see and hear but they don't understand; see Isaiah 6:8-10 and Matthew 13:10-17. Their hearts are calloused. If they understood with their hearts and turn, I would heal them! "...blessed are those who hear...and take to heart what is written...because the time is near" Rev 1:3.This book is a Bible study. The book itself is rather short, but it suggests the reading of at least 40 chapters in the Bible as well as numerous verses throughout the Bible.Developments in science and technology may help open the door to understanding. If our hearts are open; receptive to God's Word... "The Key of David" is also a key to understanding the significance of temples, churches, the body of Christ, "God: the Father, Son and Holy Spirit," etc. It can dramatically change our perspective...Several study / discussion questions are included in the book.Books in the "Revelation: Transition to New Era" Series include:1. Revelation: Transition to a New Era2. Letters to the Churches3. Good Churches4. Churches: Part Good, Part Bad5. Bad Churches6. The Key of David - This book7. The Heavenly Throne And The Sealed Book8. The Apocalypse: 7 seals Including 4 HorsemenOther books will be included when they become available.