Hoping to facilitate his political aims for unity, the emperor Justinian (527-565) vigorously pursued a policy or reconciling the monophysites to the Council of Chalcedon by sponsoring a theological program to show to show that the language of Chalcedon's definition of faith was faithful to the meaning, if not to the exact terminology of Cyril's Christological formulas. The three documents translated in this volume, "Against the Monophysites," "Concerning the Three Chapters," and On the True Faith," are significant imperial documents reflecting the conclusion reached in that theological program. They serve as an important source for setting forth fundamental philosophical principles underlying the Orthodox doctrine concerning the Person of Jesus Christ.