הרב נפתלי כהן

Rav Naftali HaKohen Katz (5409/1649–24 Tevet 5479/1719), known for generations by his sefer as the baal Semichat Chachamim, was a rav and mekubal whose wanderings carried him from Ostroh to Posen, Frankfurt, and Prague. He was born in Ostroh to Rav Yitzchak HaKohen, a descendant of the Maharal of Prague. As a young man he was seized by the Tatars and held in bondage for several years; escaping, he returned to Ostroh, married Esther Shindel, daughter of Rav Shmuel Shmelke Zak, av beit din of the city, and served there as rosh yeshiva and rav. In 5450/1690 he was called to the rabbanut of Posen, where he served until 5464/1704, sinking himself into the wisdom of kabbalah and gathering a great library of its sefarim.

From Posen he was called to Frankfurt am Main. In Tevet 5471/1711 a fire broke out in his house and consumed the whole Jewish quarter, and his accusers charged that, trusting in the power of his kameot, he had held back the ordinary means of putting it out. He was thrown into prison, and though the court cleared him — the blaze had begun with a non-Jewish lodger in his house — he regained his freedom only by laying down his office. He moved on to Prague, where the Sabbatean Nechemiah Chayun drew from him a haskamah on a work whose heretical commentaries had been kept from his eyes; when the Chacham Tzvi of Amsterdam laid the book’s true nature before him, Rav Naftali retracted the approbation, placed Chayun and his sefer under a ban, and stood among the strongest allies of the Chacham Tzvi in the war against the Sabbateans.

In 5475/1715 he traveled to August II, king of Poland, to seek his return to the then-vacant rabbanut of Posen, but the leaders of the community blocked the path. He returned to Ukraine, and in 5478/1718 set out to be oleh to Eretz Yisrael; on the way he was niftar in Constantinople, and there he was buried. His tzavaah, printed in Berlin in 5489/1729, is filled with moral instruction, and his granddaughter Rachel became the wife of Rav Yaakov Emden.

His great work is Birkat Hashem on masechet Berachot, comprising Kedushah U’Bracha, chiddushim on the masechta, and the introduction by which his name lives on — Semichat Chachamim, on the order and connection of the masechtot; so dear was this sefer to him that he directed it be buried with him. He also left Pi Yesharim, a kabbalistic gateway to Bereishit, the siddur Beit Rachel, and Meshech HaZera on Zeraim. Many rabbinic families trace their lineage through him; among his descendants stand Rav Aryeh Leib Heller, author of the Ketzot HaChoshen, and his brother Rav Yehuda Kahana, author of the Kuntres HaSefeikot.