The Oral Law includes all that Moses learned from G‑d by heart which he did not write down, but transmitted orally to his successors. This tradition passed on from generation to generation. The Oral Law also includes edicts and ordinances enacted by the sages throughout the generations, and laws and teachings extrapolated from the Torah's verses — employing methodology prescribed by Moses (as he was instructed by G‑d).

Click here for a detailed description of the course of tradition.

From Moses until Rabbi Judah the Prince (Rabbenu Hakadosh) the traditional laws were thus learnt by heart and handed down from generation to generation orally. In the 3rd century CE, Rabbenu Hakadosh realized that because of growing hardships and persecutions the Jews might not be able to retain by memory all these traditional laws, so he decided to record them. Being both a great scholar and a man of considerable means, he gathered around him the greatest scholars of his time and recorded all the traditional laws and interpretations of the Torah that they had learnt from their teachers. All this vast knowledge he arranged into six sections:

  1. Zeraim-"Seeds"-agricultural laws;
  2. Moed-"Season"-laws of Sabbath and Festivals;
  3. Nashim-"Women"-marital laws;
  4. Nezikin- "Damages"-civil and criminal laws;
  5. Kodshim- "Holy Things"-laws of Sacrifices;
  6. Taharot- "Purities" - laws of ritual purity.

Each section was further subdivided into tractates, "Mesichtot," each tractate into chapters, and each chapter into Mishnot (sub-sections).

The Mishnah was written very concisely, without much discussion or background information. Rabbenu Hakadosh's disciples later compiled the "Toseftot" and "Beraitot" where the subjects of the Mishnah are examined at greater length. The great scholars living after the redaction and completion of the Mishnah, who studied, examined, discussed and interpreted the Mishnah, were called "Amoraim" (meaning "teachers" or "interpreters").

The Mishnah was studied in the great Yeshivot of Israel and Babylon for several centuries. Finally, in the 5th century, Rabbi Ashi, one of the greatest scholars of his time, a man combining both scholarship and wealth, realizing that the growing troubles and sufferings of the Jewish people might cause many of the laws and interpretations of the Mishnah which had been handed down traditionally for many generations, to be forgotten, decided to write them down.

Together with his contemporary, Ravina, and other heads of the Yeshivot in Babylon, they gathered and compiled the Talmud (or Gemarah) — the Babylonian Talmud, which Jews hold sacred and study to this very day. Some one hundred years earlier, the scholars of Israel had already compiled and arranged the Jerusalem Talmud, which — although not as authoritative as its Babylonian counterpart — is also held sacred and studied by scholars to this day.

Rabbanan Sevurai
The scholars who lived after the redaction of the Talmud, were known as Rabbanan Sevurai (Rabbis - interpreters). They subtracted nothing from the Talmud; they merely interpreted it.

The great Babylonian scholars, successors to the Rabbanan Sevurai, were called Geonim ("geniuses"). For many years they headed the great Babylonian academies. The last one of them was Hai Gaon.

Rishonim and Acharonim
After the Geonim lived the great scholars: Rabbenu Chananel, Rabbi Isaac Alfasi, Rabbi Joseph ibn Migash, Rashi, Rambam (Maimonides) and others. Rashi (Rabbi Solomon Itzchaki) won immortal fame by his commentaries on the Torah and Talmud, without which it would now be almost impossible to understand either; and Maimonides by his Mishneh Torah ("Repetition of the Law") — a codification of all the laws of Israel. The grandsons of Rashi together with other great scholars of their time compiled the "Tosefot" commentaries on the Talmud. The scholars who lived approximately the first 500 years after the turn of the millennium are called "Rishonim" (the "first" scholars).

Various great scholars of the following years, known  as "Acharonim" ("latter" sages), gathered the final decisions and settlements of disputed laws, as codified by the Rishonim and arranged them. The most outstanding of them was: the "Author of the Turim," Rabbi Jacob son of the Rabbi Asher. Later, Rabbi Joseph Caro reexamined and recast the law-decisions and arranged them in his famous work the Shulchan Aruch, the famed Code of Jewish Law, so that every Jew could learn and understand them.

The holy Torah—the Written Torah and the Oral Torah—is the Divine gift that G‑d has given us through Moses, on Mount Sinai. This selfsame Torah was handed down by Moses to his successor Joshua, and so on from generation to generation to the present day. As G‑d is eternal, so the Torah which He has given is eternal, and through studying the Torah and observing the precepts and commandments of the Torah, the Jewish people are also eternal.