This book is an exposition of Paul’s three Prison Church Epistles: Ephesians, Philippians, and Colossians. These epistles are presented as a Trilogy: three epistles which, while complete in themselves, together form a larger work, the subject of which is the Mystery. Ephesians emphasizes the truth of the Church as the Body of Christ. Philippians presents Christ as the Mind which indwells the members of the Body. And Colossians emphasizes Christ personally as the Head of the Body.