CHORIN, AARON (1766–1844), Pioneer of Reform Judaism in Hungary. Born in *Hranice (Moravia), Chorin studied for two years in the yeshivah of Mattersdorf and then at that of Ezekiel *Landau in Prague, where in addition to his religious studies, he acquired a knowledge of general philosophy and developed an interest in Kabbalah. He was appointed rabbi of Arad in 1789, and in 1803 published in Prague his Emek ha-Shaveh, attacking those customs which he declared had no basis in Judaism, basing his reforms on rulings in the Talmud. The book caused a storm among the ultra-Orthodox, who found it heretical. Mordecai Banet of Nikolsburg appealed to the community of Arad to ban the book. Chorin was summoned to appear before a bet din who ordered the book to be burned and who compelled him to recant in writing. However, Chorin appealed to the government, which set aside the verdict. Chorin began by abrogating customs such as *kapparot and placing copies of the Psalms of Ascent near a woman in childbirth, but in the course of time he extended his reforms, particularly to the synagogal liturgy, abolishing the *Kol Nidrei prayer, changing the text of other prayers, permitting prayer in the vernacular with uncovered head, and approving the use of the organ on the Sabbath. He also curtailed the seven days of mourning and permitted riding and writing on the Sabbath. In his article, Kinat ha-Emet he supported the reforms of Israel *Jacobson; in Davar be-Itto (in Hebrew and German, 1820), he maintained that love of God and of humanity take precedence over the positive commandments; his article "Hillel" (Bikkurei ha-Ittim, 1824), which takes the form of a dialogue between *Hillel and his disciple *Johanan b. Zakkai, was written in the same spirit; in Iggeret Elasaf (Hebrew and German, 1826) he replied to questions raised by the government of Baden and the Jewish community of Karlsruhe by proposing further reforms. Toward the end of his life he supported the resolutions of the Conference of Reform Rabbis in Brunswick. Chorin also published Avak Sofer (1828), notes on the Shulḥan Arukh, Yoreh De'ah and Even ha-Ezer; Ẓir Ne'eman (1831); and Yeled Zekunim (1839), on the reform of Judaism. He was a fanatical fighter for secular education and endeavored to improve the social and cultural status of the Jews of his country by preaching in favor of the founding of a rabbinical seminary and of a school for promoting crafts and agriculture among Jews. In Orthodox circles he was contemptuously referred to as "Aḥer" (an acronym of his name "Aaron Chorin Rabbi"), the name applied to *Elisha b. Avuyah after his apostasy.
J.J. (L.) Greenwald (Grunwald), Korot ha-Torah ve-ha-Emunah be-Hungaryah (1921), 41–44; idem, Li-Felagot Yisrael be-Ungarya (1929), 7, 9–11, 14–23; R. Fahn, Pirkei Haskalah (1936), 192–6; M. Peli, in: huca, 39 (1968), 63–79, Heb. sect.; J.J. Petuchowski, Prayerbook Reform in Europe (1968), index; D. Philipson, The Reform Movement in Judaism (19673), index; W.G. Plaut, Rise of Reform Judaism (1963), index; M.S. Samet, "Halakhah u-Reformah" (Diss. Jerusalem, 1967), 188–95; L. Loew, Aron Chorin (Ger.; appeared in Ben Chananja, 4 (1861), separately 1863, reprinted in his Gesammelte Schriften, 2 (1890), 251–420); S. Bernfeld, in: Keneset Yisrael, 3 (1888), 91ff.; idem, Toledot ha-Reformaẓyon ha-Datit be-Yisrael (1900), index, s.v.; J.J. (L.) Greenwald (Grunwald), Ha-Yehudim be-Ungarya (1913), 59–63.