The worship and organization of the Christian church must be defined by the Hellenistic world in which it took root and emerged victorious over Roman Imperial paganism. The struggle of the early church to maintain a testimony and doctrine that would be faithful to the ""Rule of Faith""--which was established by the authority of certain Apostles who had the biggest impact in setting up the missional churches of the first century--and would conform to Jesus Christ's earthly ministry. Eusebia (piety) marks the Hellenistic understanding of all worship based on the relationships that are changed as a result of an encounter with a supreme being. This opens the door to explore all the aspects of Church History as a product of corporate worship. Five cities emerge in the apologetic and concilar church ages (150-850 CE) that have the greatest impact on the world of Christianity for all time. Those churches are called the Patristic churches because their bishops became the power holders of all the churches (for good or for bad). This book provides insight into the contribution of the five patriarchal cities (Jerusalem, Antioch, Alexandria, Rome, and Constantinople) to the worship, polity, doctrine, and traditions of the church. The account begins with the exegetical back-drop of the Hebrew and Greek words for worship and the impact of these in the milieu of a Jewish church and a gentile church. The study of the patriarchal leadership in the apostolic, apologetic, and concilar ages of the church marks a clear direction of the church to the beginnings of the medieval era. It clearly delineates the differences in the East and West and the struggles within the Empire to gain unity through preeminence of polity. A unique approach was taken to combine the historical events and activities of the leaders of each of the churches with motive and intent toward good or bad. It was written from a Protestant and Orthodox perspective, which adds insight to set up the spiritual and theological reasons for the Reformation that begun under Wycliffe, Huss, and later Luther. Dr. Thompson is Professor of Church History and Exegesis at Faith Evangelical Seminary, Tacoma, Washington where he has been teaching since 1996.