Twins may be allied with the celestial or animal realms: they have sometimes been construed as 'extra-human'. This multi-disciplinary work explores the imaginative sacred history of twinship, and examines the multiple ways in which the 'doubling' of a human being may be religiously and culturally expressed. Encompassing twins in the ancient Near East and Mediterranean worlds, native American spirituality, mythology and folklore and South Asian spirituality, the book offers a variety of perspectives on this fascinating topic. Subjects discussed include the great Roman foundation myth of Romulus and Remus; the significance of the twin Christian saints Cosmas and Damian; the meanings of twinship in Yoruba myths and iconography; the legacy of the twin Healer-Saints of ancient Greece, Castor and Pollux (transformed by Zeus into the constellation Gemini); and Odin's relationship with his twin ravens, Huginn and Munnin. Gemini and the Sacred makes a major contribution to a field of great cultural significance.