Based largely on the classic work by the late Rev. Walter J. Schmitz, S.S., S.T.D., published in the 1950s by the same name, this text sets forth in a clear and simple manner the correct way to celebrate Low Mass in accordance with the directions of the Antiochian Orthodox Christian ArchdioceseÕs Western Rite Vicariate. Learning to celebrate the Low Mass correctly is critical for every priest who serves the ancient Liturgy of Saint Gregory, for it is the simplest form of Mass ceremonial and therefore the necessary building block of the more solemn ceremonies of High and Solemn Mass.