Sefer HaBahir (Book of the Brightness) is an anonymous mystical work, attributed to a 1st-century rabbinic sage Nehunya ben HaKanah because it begins with the words, "R. Nehunya ben HaKanah said". It is an early work of esoteric Jewish mysticism which eventually became known as 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 Bahir’​s text, which sometimes ends discussion in mid-sentence and which often jumps randomly from topic to topic supports this claim. The historical critical study of this book points to a later date of composition. For some time scholars believed that it was written in the 13th century by Isaac the Blind, or by those in his school. The first sentence, "And now men see not the light which is bright in the skies" (Job 37:21), being isolated, and having no connection with what follows, was taken to be an allusion to the blindness of its author. However, modern scholars of Kabbalah now hold that at least part of the Bahir was an adaptation of an older work, the Sefer Raza Rabba. This older book is mentioned in some of the works of the Geonim; however no complete copies of Sefer Raza Rabba are still in existence. However, quotes from this book can still be found in some older works. Scholar Ronit Meroz argues that elements in the Bahir date back to 10th century Babylonia, as witnessed by the acceptance of the Babylonian system of vowel points, which later fell into disuse, while other elements were written in 12th century Provence. The Bahir assumes the form of an exegetic midrash on the first chapters of Genesis. It is divided into sixty short paragraphs or a hundred and forty passages and is in the form of a dialogue between master and disciples. The Bahir contains commentaries explaining the mystical significance of Biblical verses; the mystical significance of the shapes of the Hebrew letters; the mystical significance of the cantillation signs and vowel points on the letters; the mystical significance of statements in the Sefer Yetzirah and the use of sacred names in magic.