Torah is a Hebrew word generally translated as “teaching” or “instruction.” In reference to the Hebrew scriptures, Torah means the first five books, Genesis through Deuteronomy. According to tradition, Moses himself composed the whole of the Torah under divine inspiration. This ancient attribution has the benefit of lending maximum authority to the earliest sacred texts by associating them with the man most identified with the divine revelation that shaped the faith community known as Judaism. Modern scholarship has demonstrated convincingly the historical improbability of the traditional attribution. In its most general sense, Torah means revealed or divine Law—all that God requires of Jews. But as the Jewish community has grown and spread, moving into new lands and cultural settings, interpreting the scriptural Torah in practical terms has presented challenges. A highly stylized traditional reconstruction of sacred history suggests the following sequence of events.

When a group of Jews returned to Israel from exile in Babylon in the late sixth century B.C.E., many Jews no longer knew Hebrew. In the mid-fifth century B.C.E., Ezra “rediscovered” long-lost texts of scripture, but when he proposed to renew the community’s knowledge of the sacred texts, he confronted a serious problem: he would have to design a way of interpreting the Hebrew sources into Aramaic. Ezra then commissioned scholars who could translate the Torah into Aramaic as it was being read aloud to the people. That translation, or paraphrase, was itself a kind of commentary on the sacred text. Thus began the phenomenon called “oral” Torah. From the fifth century B.C.E. on, classes of scholars would oversee its elaboration. One generation would pass oral tradition down to the next until it became so extensive that it had to be written down to be preserved. Then a new class of scholars would initiate commentary on the now written “oral” law, extending the process further, until once again the burgeoning oral tradition had to be committed to writing or be lost forever. Recent research suggests, however, that even during the Babylonian exile, scholars kept the study of Hebrew sources very much alive. It turns out that Ezra and Nehemiah played a less revolutionary role in the story, and the importance of the kind of Aramaic “translation” (targum) attributed to Ezra did not arise until much later.