(Hebrew; "Book of Brightness") Hebrew commentary on the Old Testament that had a major influence on the development of the Kabbala. It also influenced the symbology of Judaism in general by calling attention to the mystical significance of the shapes and sounds of the Hebrew alphabet. The Bahir first appeared in France in the 12th century, though Kabbalists consider it much older. It introduced the concept of the transmigration of souls and the notion of a cosmic or spiritual tree that symbolizes the flow of divine creative power. Though Kabbalists view it as authoritative, mainstream Judaism rejects it as heretical