Isaac Asir HaTikvah
In two Medieval sources Isaac is referred to as the Gadol Hador, literally the "Head of the Generation", attesting to his prestigious status. Professor Elchanan Reiner believes that Isaac would have only been referred to by this title after the death of Alexander Suslin.
Isaac originally had a yeshiva in Heidelberg, Germany. Around 1350 he immigrated to Jerusalem with a group of students and founded a yeshiva. His institution in Jerusalem is mentioned in a Herem document from 1377. Among his students were Samson ben Samuel, author of Kitzur HaMordechai, and Menahem Zioni. Other students of his are mentioned in the above Herem document. Isaac's community received funding from Jewish communities in Europe.
Isaac's teachings are primarily recorded in the comments of the above student, Rabbi Samson, in his glosses to the Kitzur HaMordechai, found in the National Library of Israel Ms. Heb. 38°6697 as well as in Oxford Ms. Neubauer 784. Many of Isaac's rulings have been published by Rabbi Shlomo Spitzer. Additionally, Isaac is quoted once by Rabbi Yoel Sirkis is his commentary on the Tur.
- Reiner, Elchanan (he) (1984). ""בין אשכנז לירושלים : חכמים אשכנזים בא"י לאחר "המוות השחור" [Between Ashkenaz and Jerusalem: Ashkenazic Scholars in Eretz-Israel after the "Black Death"]. Shalem (in Hebrew). Jerusalem: Ben-Zvi Institute. 4.
- Coronel, Nathan (1864). Commentarios quinque doctrinam Talmudicam illustrantes (in Hebrew). della Torre. p. 111.
- Rabbi Isaac is quoted in Zioni's commentary on the Torah (17d in the Lemberg 1882 ed.) concerning an aspect of Gilgul.
- Yuval, Israel Jacob (1981). "Alms from Nuremberg to Jerusalem (1375-1392)" (in Hebrew). 46 (3). Jerusalem: Zion: 182–197. Cite journal requires
- "קיצור המרדכי" [Kitzur HaMordechai]. Ktiv.
- Spitzer, Shlomo (1978). "פסקי רבותינו שבאשכנז בדור הסמוך לגזירות ק״ט" [Rulings of Our Rabbis in Ashkenaz During the Generation Near the Persecutions of 1349]. Moriah (He) (in Hebrew). Jerusalem: Machon Yerushalayim (he). 8 (2–3 [86–87]).
- Hakohen, Naftali Yaʻaḳov. (1967–1970). Sefer Otsar Ha-Gedolim (in Hebrew). 5. Haifa. pp. 179–180.