Mekhilta of Rabbi Shimon ben Yochai in the context of "Nachmanides"

Shimon bar Yochai (Zoharic Aramaic: שמעון בר יוחאי, Šimʿon bar Yoḥay) or Shimon ben Yochai (Mishnaic Hebrew: שמעון בן יוחאי), also known by the acronym Rashbi, was a 2nd-century tanna or sage of the period of Roman Judaea and early Syria Palaestina. He was one of the most eminent disciples of Rabbi Akiva. The Zohar, a 13th-century foundational work of Kabbalah, is ascribed to him by Kabbalistic tradition, but this claim is universally rejected by modern scholars.

In addition, the essential legal works called the Sifre and Mekhilta of Rabbi Shimon ben Yochai are attributed to him (not to be confused with the Mekhilta of Rabbi Ishmael, of which much of the text is the same). In the Mishnah, where he is the fourth-most mentioned sage, he is referred to as simply "Rabbi Shimon" except in Hagigah 1:7. In baraitas, midrash, and gemara, his name occurs either as Shimon or as Shimon ben Yochai. An 8th-century pseudonymous attribution of divine revelations to Shimon by the angel Metatron is also known, called The Secrets of Rabbi Simon ben Yohai.

The Mekhilta of Rabbi Ishmael (Jewish Babylonian Aramaic: מְכִילְתָּא דְּרַבִּי יִשְׁמָעֵאל IPA /məˈχiltʰɑ/, "a collection of rules of interpretation") is midrash halakha to the Book of Exodus. The Aramaic title Mekhilta corresponds to the Mishnaic Hebrew term מדה middā "measure," "rule", and is used to denote a compilation of exegesis (מדות middoṯ; compare talmudical hermeneutics). Other important mekhiltas were those of Shimon bar Yochai and on Book of Deuteronomy. The latter work was also associated with Rabbi Ishmael's teachings.

According to Steven Fine, both Sifra and the Mekhilta I. were concerned with the sanctification of early study houses after the destruction of the Second Temple.