The Rationale Divinorum Officiorum is arguably the most important medieval treatise on the symbolism of church architecture and rituals of worship. Written by the French bishop William Durand of Mende (1230-1296), the treatise is ranked with the Bible as one of the most frequently copied and disseminated texts in all of medieval Christianity. It served as an encyclopedic compendium and textbook for liturgists and remains an indispensable guide for understanding the significance of medieval ecclesiastical art and worship ceremonies.

This book marks the first English translation of...