400 AD-Gemara

The Gemara (also transliterated Gemora, Gemarah, or, less commonly, Gemorra; from Hebrew גמרא‎, from the Aramaic verb gamar, study) is the component of the Talmud comprising rabbinical analysis of and commentary on the Mishnah. After the Mishnah was published by Judah the Prince (c. 200 CE), the work was studied exhaustively by generation after generation of rabbis in Babylonia and the Land of Israel. Their discussions were written down in a series of books that became the Gemara, which when combined with the Mishnah constituted the Talmud.

There are two versions of the Gemara. The Jerusalem Talmud (Talmud Yerushalmi) was compiled by scholars of the Land of Israel, primarily of the academies of Tiberias and Caesarea, and was published between about 350–400 CE. The Talmud Bavli was published about 500 CE by scholars of Babylonia, primarily of the academies of Sura, Pumbedita, and Mata Mehasia. By convention, a reference to the "Gemara" or "Talmud," without further qualification, refers to the Babylonian version. The main compilers were Revina and Rav Ashi. see Talmud.

https://en.wikipedia.org/wiki/Gemara

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