Sefer HaYashar, ( he, ספר הישר, the ''Book of the Upright'') is a famous treatise on Jewish ritual authored by

Rabbeinu Tam Jacob ben Meir (1100 – 9 June 1171 (4 Tammuz)), best known as Rabbeinu Tam ( he, רבינו תם), was one of the most renowned Ashkenazi Jewish rabbis and leading French Tosafists, a leading ''halakhic'' authority in his generation, and a gra ...

, (Rabbi Jacob ben Meir, 1100–1171). The work, which survives in a somewhat incomplete and amended form, was printed in

Venice Venice ( ; it, Venezia ; vec, Venesia or ) is a city in northeastern Italy and the capital of the Veneto Regions of Italy, region. It is built on a group of 118 small islands that are separated by canals and linked by over 400 ...

in 1544 and reprinted in

Vienna en, Viennese , iso_code = AT-9 , registration_plate = W , postal_code_type = Postal code , postal_code = , timezone = CET , utc_offset = +1 , timezone_DST ...

in 1811. It is especially concerned with reconciling apparently contradictory decisions in different sections of the

Talmud The Talmud (; he, , Talmūḏ) is the central text of Rabbinic Judaism and the primary source of Jewish religious law (''halakha'') and Jewish theology. Until the advent of modernity, in nearly all Jewish communities, the Talmud was the cente ...

and with preserving Talmud text unchanged against those who wanted to make clever emendations. This ''Sefer ha-Yashar'' was used a great deal by later Talmudists and introduced the form of literature called ''

Tosafot The Tosafot, Tosafos or Tosfot ( he, תוספות) are medieval commentaries on the Talmud. They take the form of critical and explanatory glosses, printed, in almost all Talmud editions, on the outer margin and opposite Rashi's notes. The auth ...

'' 'Additional Notes'.

Editions

* ''Sefer ha-yashar'' (Vienna, 1811). * ''Sefer ha-yashar le-rabenu Tam'', ed. Simon Solomon Schlesinger (Jerusalem, 1959). Critical edition of first section (''novellae'' = Hebr. ''hiddushim''). * ''Sefer ha-yashar'', ed. Ferdinand Rosenthal (Berlin, 1898; repr. Jerusalem, 1975). Critical edition of second section (

responsa ''Responsa'' (plural of Latin , 'answer') comprise a body of written decisions and rulings given by legal scholars in response to questions addressed to them. In the modern era, the term is used to describe decisions and rulings made by scholars i ...

External links

Jewish Encyclopedia: Jacob ben Meïr Tam: The "Sefer ha-Yashar."
Rabbinic legal texts and responsa Jewish medieval literature {{Judaism-book-stub