Triennial cycle

The Triennial cycle of Torah reading may refer either a) to the historical practice in ancient Israel by which the entire Torah was read in serial fashion over a three-year period, or b) to the practice adopted by many Reform, Conservative, Reconstructionist and Renewal congregations starting in the 19th and 20th Century, in which the traditional weekly Torah portions were divided into thirds, and in which one third of each weekly "parashah" of the annual system is read during the appropriate week of the calendar.

There are 54 parashot in the annual cycle, and 141, 154, or 167 parashot in the triennial cycle as practiced in ancient Israel, as evidenced by scriptural references and fragments of recovered text. By the Middle Ages, the annual reading cycle was predominant, although the triennial cycle was still extant at the time, as noted by Jewish figures of the period, such as Benjamin of Tudela and Maimonides. Dating from Maimonides' codification of the parashot in his work Mishneh Torah in the 12th Century CE through the 19th Century, the majority of Jewish communities adhered to the annual cycle.

In the 19th and 20th Centuries, many synagogues in the Reform, Conservative, Reconstructionist and Renewal Jewish movements adopted a triennial system in order to shorten the weekly services and allow additional time for sermons, study, or discussion.

The introduction of public reading of the Torah by Ezra the Scribe after the return of the Jewish people from the Babylonian Captivity is described in Nehemiah Chapter 8. Prior to Ezra, the mitzvah of Torah reading was based on the Biblical commandment of Hakhel (Deuteronomy 31:10–13), by which once every 7 years the entire people was to be gathered, "men, women and children," and hear much of Deuteronomy, the final volume of the Pentateuch, read to them (see the closing chapters of the Talmudic Tractate Sotah). Traditionally, the mitzvah of gathering the people and reading them the Torah under Hakhel was to be performed by the King. Under Ezra, Torah reading became more frequent and the congregation themselves substituted for the King's role. Ezra is traditionally credited with initiating the modern custom of reading thrice weekly in the synagogue. This reading is an obligation incumbent on the congregation, not an individual, and did not replace the Hakhel reading by the king. The reading of the Law in the synagogue can be traced to at least about the second century B.C., when the grandson of Sirach refers to it in his preface as an Egyptian practise; it must, therefore, have existed even earlier in Judea.

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