The messages to the 7 churches that Jesus delivered in Chapters 2 and 3 of the Book of Revelation represents 7 periods of church history that were to follow each other in regular order. The diagram shows a wonderful correspondence between the 7 periods of church history with almost 2000 years of human history since the Church Age began. The Church of the "First Born" depicted in the diagram represents all the members of the Body of Christ, i.e., believers who are born-again or spiritually regenerated. The Church of the "First Born" represents the true, invisible church, set apart from the rest of religious, visible Christendom [Protestantism, Roman Catholicism, Greek Orthodox, etc.].