The Jewish religious tradition recognizes that the the Written Torah [Torah she-bikhtav] is accompanied by the Oral Torah {Torah she-b'al-Peh]. The Written Torah consists of the Five Books of Moses [Pentateuch, in Greek; Chamishah Chumshei Torah, in Hebrew}, which are the first five books of the Hebrew Bible [Tanakh].

Jewish tradition has found within these books six hundred and thirteen commandments [Taryag mitzvot], which are the foundations upon which the whole structure of Jewish religious and ethical behaviour is built and developed. The whole gamut of traditional religious and ethical behaviour-patterns that are deemed binding are termed halakhah, which now has the equivalence of the word 'law', but whose etymology comes from the idea of 'the way we go', the way we do things in accordance with Torah. Also any individual item in this massive programme is termed 'a halakhah'.

While the written Torah is the ultimate basis of Jewish tradition, for halakhic purposes it must be interpreted and understood in the light of the Oral Torah. Any halakhah that comes more or less directly from the Written Torah is termed 'de-Oraita' ['from the Torah' in Aramaic], whereas any halakhah that comes from rabbinic innovation or expansion is termed 'mi-de-rabbanan' ['from the rabbis' in Aramaic].

The origins of this process are lost in the mists of antiquity. The process first emerges into a clearer light in the centuries after the establishment of the Second Commonwealth in Eretz-Israel after the Return from the Babylonian Exile. The first returnees arrived back in Judah in the year 536 BCE; by the year 516 BCE the 2nd Bet Mikdash had been completed; around the year 444 BCE massive religious and social reforms were undertaken under the leadership of Ezra and Nehemiah, and these reforms are probably the seeds from which rabbinic Judaism was to develop over the next few centuries.

By the beginning of the second century BCE the whole system had the loyalty and affection of a plurality of the people - so much so that when the hellenising colonial pretensions of the Syrian mini-empire centered on Antioch threatened to overtake Judaism and Judah, the people rose up in revolt. This story is celebrated annually at Chanukah time. A century and a quarter of independence under the Hasmonean dynasty and Herod came to an end with the Roman occupation of Eretz-Israel. This time, when the people finally broke into open revolt they were completely defeated by the Roman military machine and the Bet Mikdash was destroyed - in the year 70 CE.

During all this time the Oral Torah had been growing steadily. The complete eclipse of the Bet Mikdash and its ritual after 70 CE gave a new impetus to the growth and development of the Oral tradition. The ancient Sanhedrin was re-established in Yavneh, where rabbis from all over the country met to discuss the details of the Oral Tradition and to decide, by majority vote, what was binding.

It was probably Rabbi Akiva, at the end of the first century CE and at the beginning of the second century, who was the first to reassemble all the midrashim in a more orderly form. Until his time the midrashim were ordered around the verses of the Written Torah that had been their origin. As the system burgeoned this became more and more unwieldy, and Rabbi Akiva began to reorder these Midreshei-Halakhah according to their content, rather than according to their precedence in the Written Torah. This new system he called Mishnah, a term which comes from the Hebrew verb 'to learn by rote'. We recall that all this material was still passed on by word of mouth!

Rabbi Akiva's system of Mishnah (as opposed to Midrash) was developed and honed by his students and successors during the tumultuous second century. By the time we reach the end of the second century and the start of the third century the time was ripe for a new and decisive development. Rabbi Yehudah, the son of Rabban Shimon ben-Gamli'el, was now the President of the Sanhedrin. His personality and status guaranteed his ascendancy. In modern terms he was a multi-millionaire, on excellent personal terms with the Imperial house in Rome, a man of international culture who would only permit Hebrew or Greek to be spoken in his 'residence'. He had the necessary sway and halakhic expertise to make the much-needed change - though not without some vociferous opposition. He set down in writing his own personal Mishnah and published it. Rabbi Akiva's mishnah had developed into the mishnah of Rabbi Me'ir, which had become Rabbi Yehudah's mishnah, which now became 'The Mishnah' [around 200 CE].

The Mishnah is divided into six Sedarim [Orders, or volumes], each Seder dealing with a different aspect of the Oral Torah - Eretz-Israel, Holy Days, Family Law, Civil Law, Bet-Mikdash and Ritual Purity. Each Seder is divided into Massekhtot [Tractates], each tractate dealing with a more particularized issue within the general compass of the seder: for instance the Seder that deals with Family Law has Massekhtot [tractates] on Marriage, Marriage Contracts, Divorce, Levirate Marriage and so forth. The tractates are divided into chapters and the chapters into small manageable units each one of which is called a mishnah or a halakhah.

The sages whose discussions and views are enshrined in the Mishnah as given the generic description of Tanna'im, and, usually, the individual title of Rabbi. The age of the Tanna'im also produced other works - in particular we should mention the Tosefta and the halakhic midrashim called Mekhilta, Sifra and Sifré. The Tosefta is a work that mirror-images the Mishnah but contains halakhot that Rabbi Yehudah excluded from his Mishnah: these are called 'baraitot', which comes from the Aramaic for 'an excluded mishnah'. The Mekhilta contains halakhic midrashim on the book of Exodus, the Sifra on the book of Leviticus, and the Sifré on the books of Numbers and Deuteronomy. The age of the Tanna'im is deemed to come to an end with the death of Rabbi [Yehudah] in the year 217 CE.