גרשון חנוך הניך ליינר

Rav Gershon Chanoch Henoch Leiner of Radzyn (21 Sivan 5599/1839 – 4 Tevet 5651/1890) was the third Rebbe of the Izhbitza–Radzin dynasty and a prolific author, known as the Baal HaTechelet and, in Radzin, as the Orchot Chaim after one of his sefarim. His father was Rav Yaakov Leiner, the second rebbe of the line; his grandfather was Rav Mordechai Yosef Leiner, the Mei HaShiloach, to whom he was close and whose Torah he wrote down — publishing it at about twenty in the sefer Mei HaShiloach. On his father’s passing in 5638/1878 he succeeded him as rebbe of Izhbitza-Radzin and rav of Radzyn.

At sixteen he conceived his great project: a Gemara-like work on the mishnayot of Seder Taharot, on which there is no Talmud Bavli. He gathered the relevant material from across the Bavli, the Yerushalmi, and the beraitot and arranged it in order, with a short and a long commentary in the manner of Rashi and Tosafot and cross-references down the margins. Only his volumes on Kelim and Oholot appeared, as Sidrei Taharot; the rest remained in manuscript and were lost in the Holocaust. Its very form — laid out like a daf of Gemara — and its challenges to the emendations of the Vilna Gaon stirred sharp opposition among the rabbanim of Lita, who issued public warnings against it; the later volume on Oholot carried a note that it was a compilation, not a new Talmud, and drew approbations from Rav Yitzchak Elchanan Spektor and others.

An autodidact who taught himself Latin, medicine, and the sciences, he labored above all to restore the techelet of tzitzit. He traveled to Italy four times, studied the sea creatures at the great aquarium in Naples, and concluded that the dye had come from the common cuttlefish; he set out his findings in Sfunei Temunei Chol, Psil Techelet, and Ein HaTechelet, and by his account some twelve thousand Jews in Poland took on the mitzvah. The claim met wide opposition, though a few gedolim, such as the Maharsham, wore it, as do many Breslover chassidim to this day; years later Rav Yitzchak Isaac HaLevi Herzog examined the dye and showed it to be Prussian blue.

He was niftar in Radzyn on 4 Tevet 5651 and buried in the town’s Jewish cemetery; his only son, Rav Mordechai Yosef Elazar Leiner, took his place.