This book covers "a great and profound matter, the divine Spirit with the human spirit in the Epistles, from Romans through the book of Revelation. The Epistles come after the four Gospels and the Acts. The Gospels are a full record of the Lord Jesus Christ--who He is, what He did, what He accomplished, and what He attained. After this, the Acts gives us a record of the spread, the propagation, of this Christ, which is the church as the Body of Christ. In the four Gospels we have the Head, and in the Acts we have the Body, the propagation and continuation of the Head. After this, the twenty-two books from Romans to Revelation present a full definition, explanation, and revelation of the wonderful and mysterious economy of God."