ר' ישראל איסרלין

Rav Yisrael Isserlein ben Petachia Ashkenazi (5150/1390–5220/1460), the Mahari, known as Terumat HaDeshen after his sefer, was among the greatest of Ashkenazi Jewry in the fifteenth century, standing among the last of the rishonim or the first of the acharonim. His rulings are cited thousands of times in the halachic literature after him. He was born about 5150/1390 to Rav Petachia, a grandson of Rav Yisrael of Krems, author of the Hagahot Ashri.

He was first taught by his mother’s brother, Rav Aharon Blumlein, in Krems and Vienna, until the Vienna Gezera of 5181, in which his uncle was killed and his mother put to death. Forced by persecution to leave Germany, he went first to Italy and then settled in Austria, serving as rav of Brno, of Marburg, and finally of Wiener Neustadt, where he headed the local yeshiva. The Radvaz describes him as a great and authorized rav upon whom all the regions of Israel relied. He was a gifted darshan who led the davening on the Yamim Noraim; his wife, Sheindlin, rendered one of his responsa on hilchot niddah into Yiddish.

The Terumat HaDeshen’s first part gathers 354 responsa — the numerical value of deshen — across every area of halachah, with a second part, Pesakim u-Ktavim, of 267 rulings collected by his talmidim. The work is a principal source for the customs of Ashkenaz, and the Rema drew on it many times in his glosses on the Shulchan Aruch. He also wrote Biurei Mahari on Rashi’s commentary to the Torah, 36 She’arim on issur v’heter, and glosses on the Sha’arei Dura. His talmid Rav Yosef ben Moshe recorded his teachings, customs, and life in the Leket Yosher. He was niftar in Wiener Neustadt in 5220/1460.