This book examines the theology of icons in the eighth century, the most critical period in the evolution of the Eastern Church's teaching on images. The principal source is provided by the acta of the Seventh Ecumenical Council of 787.The political circumstances which led to the outbreak of the controversy over icons are discussed in detail but the main emphasis is on the theological arguments and presuppositions of the participants in the council. Major themes include the nature of tradition, the relationship between image and reality and the place of christology.Ultimately the argument over icons was about the accessibility of the divine. Icons were held by the iconophiles to communicate a deifying grace which raised the believer to participation in the life of God.