Raba or Raba Ben Joseph Ben Hama(c. 280-352) was a Jewish Talmudist who lived in Babylonia, known as an amora. His top student was the famous Abaye. The latter was head of the yeshiva academy at Pumbedita. Raba founded a new school at Machuza, which eventually became the only academy in Babylonia during his life. The development of Talmudic law (or Halakhah) was much indebted to him. He influenced all branches of Jewish learning. Wikipedia
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