||First four chapters of the novellae of Rabbenu Asher (Rosh, R. Asher ben Jehiel) on tractate Pesahim accompanied by the commentaries of R. Jacob Leib ben Mordecai Ashkenazi, entitled Sha’ar Asher and Gevul Asher. The title page includes a dedication to his mother Beila who, in addition to her many qualities, provided funds for publication of this volume. Also mentioned is his wife Zelda. R. Jacob Leib was also the author of a similar work on tractate Niddah (Brno, 1789). There are approbations from R. Asher Lemel ha-Levi, R. Benjamin Wolf ha-Levi ben Samuel Kalin, and R. Benjamin Wolf Eger ben Akiva, an introduction form R. Jacob Leib, and the text. Rabbenu Asher is in the center of the page in square letters, Sha’ar Asher along the inner margin and Gevul Asher along the outer margin, both in rabbinic letters.
Rabbenu Asher (Rosh, R. Asher ben Jehiel, c. 1250–1327) was one of the most prominent of the Medieval German talmudists. His first teachers were his father, one of the Hasidei Ashkenaz, who was a follower of Judah b. Samuel he-Hasid, and his elder brother. He spent some time in France, apparently in Troyes and then lived in Cologne and Coblenz. From there he moved to Worms, where his teacher Meir b. Baruch of Rothenburg had been appointed rabbi in 1281. Meir esteemed his pupil, and appointed him a member of the local bet-din. After the imprisonment of Meir, Asher became the acknowledged leader of German Jewry and headed the unsuccessful efforts to obtain his master's release, toward which he was prepared to contribute a considerable portion of his assets. He distinguished himself for his activities during the period of the Rindfleisch massacres (1298), and for his decisions on matters arising from the resulting disruption of family and communal life. Fearing a similar fate to that of Meir of Rothenburg, Asher left Germany in 1303. The following year, he reached Barcelona, via north Italy and Provence, where he was welcomed with great honor by Solomon b. Abraham Adret. In 1305 he accepted the position of rabbi in Toledo. His son, Judah, relates that shortly thereafter, Asher turned down a request of the German authorities that he return to his native country, for which they were prepared to provide an imperial letter of safe-conduct and an escort of 50 soldiers.
Asher was drawn into the contemporary conflict concerning the study of philosophy. In Provence he had found only "isolated individuals" engaged in exclusive study of the Torah, which fact he attributed to the widespread study of philosophy. From Barcelona he sent a letter of encouragement to Abba Mari Astruc, a leader of the opponents of philosophy. Alive to the danger of discord, he proposed an intercommunal conference to reconcile the opposing views (Minhat Kena'ot, 51). When Solomon Adret proposed a ban on the study of philosophy by anyone under the age of 25, Asher, already in Toledo, influenced the local leaders to support this ban. His vast influence and moral stature enabled him to overcome the difficulties which he encountered in those activities, and his spiritual influence was acknowledged even by the Castilian queen, Maria de Molina.
His responsa sometimes reflect the modesty and humility that typified the German school, and at others, the firmness and authority of one speaking in the name of the supreme political and judicial body of Spanish Jewry. Asher introduced into Spain the system of study of the tosafists and tried to establish a German minhag. He is regarded as one of the outstanding halakhic authorities who put the final seal to the work of the German and French codifiers, joining to it the Spanish halakhah. True to the methods of the tosafists, he subjected the statements of the rishonim and geonim to a critical examination and did not hesitate to disagree with them whenever talmudic sources did not support their view and conclusions. Virtually all the communities of Spain referred their problems to him and students flocked to his yeshivah from all Europe, including Russia. When he encountered matters not specifically prohibited in the Torah, Asher was prepared to abandon his own opinion in the face of strong opposition, particularly for the sake of peace, but he never hesitated from taking a strong stand against undesirable developments in the communal life.
His halakhic works are: (1) Piskei ha-Rosh (also called Hilkhot ha-Rosh, Sefer ha-Asheri), modeled on that of Alfasi. In it he sums up the decisions of the earlier codifiers and commentators. (2) Responsa (Constantinople, 1517). The extant collection numbers over 1,000 responsa, arranged in 108 chapters, subdivided into sections. They are of the utmost significance in the study of halakhic development and give an insight into the cultural life of Spanish and German Jewry. (3) Commentary on the Mishnayot to the orders of Zera'im being mainly an abridgment of the commentary of Samson b. Abraham of Sens to these orders.
Asher's piety and exemplary conduct are reflected in his celebrated work, known variously as Hanhagot ha-Rosh, Orhot Hayyim and Zavva'at ha-Rosh (Venice, 1579). It includes 131 ethical sayings grouped for each of the six weekdays, in which he details rules of conduct for a Jew in his private, family, and public life, and in relation to Jews and Gentiles. He demands integrity, courtesy, and sincerity in dealings with Gentiles. In 1965 the Institute for Research in Jewish Law of the Hebrew University published a comprehensive index to Asher's responsa. The index includes lists of all biblical, talmudic, and post-talmudic sources quoted in the responsa.