Biography
Rabbi Shemaryah ben Mordechai of Speyer (שמריה בן מרדכי) was a rishon of Ashkenaz and one of the Baalei HaTosafot, active in the first half of the twelfth century. He learned under Rabbi Eliezer ben Meshullam, Rabbi Eliezer Chazan of Speyer, and was a talmid-chaver (a student who was also a colleague) of Rabbi Yitzchak ben Asher, the Riva.
He was held to be a leading authority on halacha in practice and on religious custom, a baal maasim, and he most likely wrote pesakim of his own. He exchanged questions with Rabbeinu Tam and with the Raavan; the Or Zarua on Bava Batra brings a difficult question on which Rabbeinu Tam consulted him. Together with Rabbi Avraham, son of Rabbi Shmuel HaChasid, he is counted among the Chachmei Speyer (the rabbis of Speyer).
His best-known talmidim were Rabbi Yehudah ben Kalonymus of Speyer, author of Yichusei Tannaim VaAmoraim, and Rabbi Yehudah ben Kalonymus of Mainz, the father of Rabbi Elazar of Worms. The first of them usually calls him mori hayashish, “my aged teacher”, which suggests that he lived to an old age.
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Where traditions differ. Some describe him as the Riva's talmid, others as his talmid-chaver.
הרב שמריה בן מרדכי משפייר מבעלי התוספות היה תלמיד חבר לריב"א, ותלמידו של רבי אליעזר בן משולם.
Shemariah ben Mordecai was a German rabbi and tosafist of the first half of the 12th century, who was a pupil of the tosafist Isaac ben Asher. He was considered an especially eminent authority on religious rites, and seems to have written posḳim (decisions); no less a person than Jacob b. Meïr Tam consulted him about difficult question.
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