It was in the Tannaic period that the Zohar, the most famous text of Kabbalah, was committed to writing by Rabbi Shimon Bar Yochai (also known as the Rashbi). Rashbi lived in tumultuous times when the Roman government was executing all the great Torah teachers, including his master Rabbi Akiva.
Rashbi himself had to flee Roman persecution and hid in a cave with his son, Rabbi Elazar, for thirteen years. During this time, he received Divine Inspiration (Ruach Hakodesh) and merited the revelation of Elijah the Prophet and composed the sacred Zohar.
Based on the five books of Moses and written in Hebrew Aramaic, the text of the Zohar explores and expounds in a most cryptic way the mystical tradition. Its pre-eminent place in Jewish mysticism does not derive solely from its antiquity or its authorship. Other works of the Kabbalah such as Sefer Yetzirah and Sefer HaBahir are of earlier origin. The Zohar’s importance must rather be attributed to its comprehensiveness.
It became the source for practically all the later authoritative Kabbalistic teachings of the Arizal and others.
The Zohar was concealed for many centuries, and the study of the Kabbalah was restricted to a select few qualified individuals. It became revealed only in the thirteenth century and was published by one of the leading Kabbalists living in Spain, Rabbi Moshe de Leon. Some believed that the Ramban (Rabbi Moshe ben Nachman c.1194-1270 C.E.), himself a renowned Kabbalist, had sent the Zohar from Israel by ship to his son in Catalonia, but the ship had been diverted and the texts ended up in the hands of Rabbi Moshe de Leon. Others explained that these manuscripts had been hidden in a vault for a thousand years and had been discovered by an Arabian king who sent them to Toledo to be deciphered. Still others maintained that Spanish conquistadors had discovered the manuscripts of the Zohar among many others in an academy in Heidelberg. Whichever theory is true, the text was accepted as authentic by all pre-eminent Jewish scholars.
The mystics ascribe special potency to the study of Zohar.
It effects a nullification of evil decrees, eases the travails of exile, hastens the redemption, and draws forth Divine blessings. In some mystical circles, great merit is attributed to the mere recitation of the sacred texts of the Zohar, even though one does not understand them. However, ideally an effort is to be made to understand and comprehend the texts. The text has been translated into Hebrew and English. In truth, today it still remains a closed text without many introductions, explanations, and elucidations of later masters.
In summary, at this stage of history the major texts of Sefer Yetzirah, the Sefer HaBahir, the Pirkei Heichalot Rabati, and the Zohar contained the basic teachings that had been passed down through the prophets and sages from Moses. And yet, although committing the mystical tradition to writing had saved it from extinction, it was still a closed book to all but one who would be familiar with the intricacies of the esoteric tradition. The outline had been written but the keys to the tradition remained oral and contained within a small circle.
This remained the case until the next great explosion of Kabbalah to take place in the town of Safed, located in northern Israel, in the sixteenth century.