Hebrew Mysticism by Annie Besant

Nor were the Hebrews without their secret knowledge and their Schools of Initiation. The company of prophets at Naioth presided over by Samuel [I Sam., xix, 20. ] formed such a School, and the oral teaching was handed down by them. Similar Schools existed at Bethel and Jericho,[ II. Kings, ii, 2, 5 ] and in Cruden's Concordance [Under "School".] there is the following interesting note: "The Schools or Colleges of the prophets are the first [schools] of which we have any account in Scripture; where the children of the prophets, that is, their disciples, lived in the exercises of a retired and austere life, in study and meditation, and reading of the law of God. . . These Schools, or Societies, of the prophets were succeeded by the Synagogues". The Kabbala, which contains the semi-public teaching, is, as it now stands, a modern compilation, part of it being the work of Rabbi Moses de Leon, who died A.D. 1305. It consists of five books, Bahir, Zohar, Sepher Sephiroth, Sepher Yetzirah, and Asch Metzareth, and is asserted to have been transmitted orally from very ancient times — as antiquity is reckoned historically. Dr. Wynn Westcott says that "Hebrew tradition assigns the oldest parts of the Zohar to a date antecedent to the building of the second Temple"; and Rabbi Simeon ben Jochai is said to have written down some of it in the first century A.D. The Sepher Yetzirah is spoken of by Saadjah Gaon, who died A.D. 940, as "very ancient". [ Dr. Wynn Westcott, Sepher Yetzirah, . ] Some portions of the ancient oral teaching have been incorporated in the Kabbala as it now stands, but the true archaic wisdom of the Hebrews remains in the guardianship of a few of the true sons of Israel.