Gershon Henoch Leiner

Grand Rabbi Gershon Chanoch Henech Leiner of Radzin (1839–1891), son of Beis Yaakov, author of Orchos Chayim, Sod Y'sharim, Tiferes Hachanochi, and Dalsos Shaar Ha'ir, among many other seforim.

The Rebbe is referred to by Radziner Chasidim as the Orchos Chayim, based on his phenomenal work on the Tzava'ah - the will - of the Tana Rabbi Eliezer HaGadol. This work was written by the Rebbe basically without any open books to his advantage, in only 12 days, during his trial on a libel fabricated against him by his adversaries. When the Rebbe published this work, he commented to his chasidim that he's happy that he got to print his Tzava'ah.

In the larger world the Rebbe is better known as the Ba'al HaTecheiles. The Rebbe was brilliant in both the revealed and the hidden Torah. He was also extremely knowledgeable in several scientific fields, like chemistry, engineering and medicine. He spoke several languages fluently, and used them frequently while prescribing medicines in Latin to the countless people who turned to him for help. At the age of sixteen, the Rebbe had already formulated a spectacular idea: he would compose a "gemara" of a sort on the mishnayos of Seder Taharos, as there is no Talmud Bavli on those tractates. In order to accomplish this, he gathered all the relevant material from the whole Talmud Bavli, Talmud Yerushalmi, and all other Braysos etc., and presented them in chronological order in a sefer he called Sidrei Taharos on Maseches Keilim. He later did the same with all the other tractates of Seder Taharos. However, only his works on Keilim and Oholot were published. (The other tractates were lost during The Holocaust). The task took him ten years to complete.

He worked tirelessly for the restoration of the techeiles of the tzitzis. He made use of his vast knowledge to research the topic, and traveled to Italy four times to conduct his study. While there he visited what was then the largest aquarium in the world, in the coastal city of Naples, and upon studying the different sea creatures, he came to the conclusion that the original blue color for the Techeiles was extracted from the secretion of the Sepia officinalis (a type of squid known as the common cuttlefish; in Hebrew known as the Dionon). Legend has it that on one of the Rebbe's visits to Rome; he succeeded in persuading the Vatican to allow him a quick glimpse of the Holy Vessels of the Beis HaMikdosh, to match his findings with the techeiles on the priestly garments. He published several books on the topic, such as S'funei T'munei Chol, P'sil T'cheles, and Ein HaT'cheles, and succeeded in influencing many Gedolim with his work. At the same time, there were Gedolim who opposed to the Rebbe's opinion and did not agree with his findings. There was, however, a small number of Gedolei Yisrael who would practice the rediscovered mitzvah of techeiles, like Rabbi Sholom Mordechai Schwadron (known as the Maharsham of Berzan) who possessed a tallis with techeiles fringes. All the Rebbe's chassidim and followers wore them, as do many Breslov chassidim to this day.

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