Rabbi Shimon bar Yohai, Shimon son of Yohai, Simon son of Yohai or Rashbi (pronounced "Rash-bee", an acronym from Rabbi Shimeon bar Yochai.), was a famous rabbi who lived in the era of the Tannaim (scholars of the Mishnah) in the area of what is today Israel during the Roman period, after the destruction of the Second Temple in 70 CE. He was one of the most eminent disciples of Rabbi Akiva, and is attributed by many with the authorship of the Zohar ("The Brightness"), the chief work of modern-day Jewish mysticism. In addition, the important legal homilies called Sifre and Mekhilta are attributed to him. In the Mishnah, he is often referred to as simply "Rabbi Shimon."
Rabbi Shimon bar Yochai, was a student of Rabbi Akiva, who was the spiritual leader of the Bar Kochva Revolt against Rome. Rabbi Shimon Bar Yochai is one of the most important sages in Jewish history, lived over 1800 years ago.
Rabbi Shimon bar Yochai acquired a reputation as a worker of miracles, and on this ground was sent to Rome as an envoy, where (legend tells) he exorcised from the emperor's daughter a demon who had obligingly entered the lady to enable Rabbi Shimon to effect his miracle.
This rabbi bore a large part in the fixation of law, and his decisions are frequently quoted. To him were attributed the important legal homilies called Sifre and Mekhilta, and above all the Zohar, the main work of the Kabbalah.
The fullest account of Rabbi Shimon's teachings is to be found in W Bacher's Agada der Tannaiten, ii. pp. 70-149. When the Talmud attributes a teaching to Rabbi Shimon without specifying which Rabbi Shimon is meant, it means Shimon bar Yochai.