His Responsa
As director of the academy he sought to reach pupils both near and far, and many of his responsa have been preserved in the geonic collections and in the works containing the earlier decisions. His responsa are similar to the geonic responsa in general, a majority of them dealing with questions of religious practise, though some of them contain expositions and comments on passages of the Talmud and the Mishnah.
Indeed, his literary activity was confined to Talmudic and to related subjects. He was not greatly interested in Arabic literature, although he knew enough Arabic to be able to write in that language those of his decisions that were addressed to communities in Muslim countries. Generally he preferred to use Hebrew or Aramaic for that purpose.
Sherira was noted for the nobility and seriousness of his character. As a judge he endeavored to arrive at the exact facts of a case and to render his decisions in strict conformity with the Law. In deciding practical questions he adopted the more rigorous view, following the letter of the Talmud with the purpose of upholding and emphasizing its authority against the attacks of the Karaites. He frequently formulates in his responsa rules which are highly important for the correct interpretation of the Talmud. For instance, he declares that the term "miẓwah" designates in some passages a command that may not be broken with impunity, but in other passages denotes merely an admonition with which it would be commendable to comply, but which may be disregarded without fear of punishment ("Teshubot Ge'one Mizraḥ u-Ma'arab," No. 141, in "Bet Talmud," iv. 351).
Sherira was a student of cabalistic mysticism; he believed that the mystical works "Shi'ur Komah" and "Hekalot" represented ancient traditions, originating with R. Ishmael and R. Akiba. He says in a responsum ("Sha'are Teshubah," No. 122) that the passage in "Shi'ur Ḳomah" ascribing human organs to God embodies profound mysteries, but must not be taken literally. Sherira wrote a work on the Talmud, under the title "Megillat Setarim." In this work he seems to have discussed the importance of the Aggadah (Aboab, introduction to "Menorat ha-Ma'or"); but the portion of the work containing his opinions on this subject has been lost.
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