This is the third volume of a detailed and systematic exposition of the history, canonical structure, doctrine, moral and social teaching, liturgical services, and spiritual life of the Orthodox Church. The purpose of this series is to present Orthodox Christianity as an integrated theological and liturgical system, in which all elements are interconnected. Theology finds its expression and is shaped in the liturgical experience and church art—including icons, singing, and architecture. The services, in their turn, influence the ascetic practice and the personal piety of each Christian; they shape the moral and social teaching of the Church as well as its relation to other Christian confessions, non-Christian religions, and the secular world. Volume One focused on the history and canonical structure of the Orthodox Church, Volume Two on the fundamental teachings of the Church, grounded in Scripture and Tradition. This third volume delves into the unique aspects of Orthodox art as expressed in its architecture, icons, and liturgical music. This includes a detailed examination of the theology of icons and their historical use by the Church through the centuries. The last section traces the importance and liturgical function of music as it developed in both Byzantine and Slavic Orthodoxy. Metropolitan Hilarion Alfeyev has authored numerous works on theology and church history, and is an internationally recognized composer of liturgical music. In the words of Patriarch Alexei II of blessed memory, “His many years of service to the mother church, his rich creative activity, and his broad perspective enable him to present the tradition of the Orthodox Church in all its diversity.”