The Gnostic Mass – Theodor Reuss’s Version of a Thelemic Classic. This volume offers another perspective on the holiest of Thelemic rituals. While Aleister Crowley’s Liber XV: The Gnostic Mass remains the most well-known version of the Gnostic Catholic liturgy, Theodor Reuss’s 1920 edition presents a unique and modified liturgical vision—one that reflects his synthesis of Gnostic Templar mysticism, cosmic love, and social responsibility. This is not a straight translation of Crowley’s work but an independent, ritually and theologically revised version. Reuss merges Gnostic Christianity with occult symbolism, sexual mysticism, and ethical-spiritual ideals, creating a distinct expression of the ritual. Theodor Reuss (1855–1923), a German occultist, freethinker, and the modern restorer of Ordo Templi Orientis (O.T.O.), blended Crowley’s Thelema with European Gnosticism, early Christian liturgy, and Tantric philosophy, forging a singular spiritual synthesis. This volume is essential for anyone seeking to understand the alternative roots of The Gnostic Mass—and a must-have for collectors of ritual texts, as well as students of Gnosticism, Thelema, and the esoteric tradition.