Sefer HaBahir (The Book of Brightness) is an anonymous, pseudoepigraphic mystical work, attributed to first-century rabbinic sage Nehunya ben HaKanah. Modern scholars date the esoteric, theosophical work to the beginning of the 13th century, amongst an unidentified circle of medieval Ashkenazic esotericists, and posit that its emergence marks the literary debut of Kabbalah. Medieval kabbalists write that the Bahir did not come down to them as a unified book but rather in pieces found in scattered scrolls and booklets. The scattered and fragmentary nature of the text, which sometimes ends a discussion mid-sentence and jumps randomly from topic to topic, supports this claim. While the work likely contains an older core — perhaps in the Babylonian East — passages accrued, and the work, as it has come down to us, contains 140 passages. The work’s speculations about the Divine are in the form of commentary and interpretation of biblical passages.