Son of Rav Mordechai Twerski of Czernoble (Tshernoble). Born in 1792 (תקנ"ב), others say 1794 (תקנ"ד). Third son from the eight sons of the Czerbobler Maggid. Son-in-law of Rav Dov Ber Schneerson of Lubavitch, the Mittler Rebbe of Chabad.
For two years, he remained in Liadi until the Baal HaTanya’s passing. Afterwards, he moved to Lubavitch and remained at his father-in-law, the Mittler Rebbe’s table. There, he studied with the Tzemach Tzedek who testified that “Before Rav Yaakov Yisroel recites Kiddush on Shabbos, Eliyahu HaNavi himself delights with him.” After the Mittler’s passing on 9 Kislev תקפ"ח, Rav Yaakov Yisroel returned to Czernoble to his father’s home.
In תקצ"ד, Rav Yaakov Yisroel served as Horonsteipler maggid and rebbe in his own father’s lifetime - indeed, at his father’s behest. A dispute developed involving his elder brother, Rav Aharon of Czernoble, and his handling of the tzedakah monies for Eretz Yisroel. Although his other brothers Rav Yitzchok of Skver and Rav Yochanon of Rachemstrivka tried to make peace between them, their efforts failed. Rav Yaakov Yisroel left Horensteipel for Tsherkas and as a result, the conflict somewhat abated.
He left behind four daughters: Freida, the wife of Menachem Nachum Schneerson of Niezon; Tsherna, the wife of Meshulam Zisha Auerbach of Tlumatsh; Chana, the wife of Yosef Yitzchok Schneerson of Avritsh; and the wife of Rav Naphtali Halberstam of Shinova. His manner was unique, and was different from his seven brothers in that the Torah of Chabad he absorbed from his in-laws was woven together with the facets of Czernoble. This is evident in his sefer, Shoshanas HaAmakim, part one of which he named, Emek Tefillah. The second part was never completed by the Tsherkaser, and his grandson Rav Mordechai Dov Twerski of Horensteipel completed it and named it Emek HaChochma which is derushim and pilpulim on the parshah.
He passed away on the 13th of Elul, 1876 (תרל"ו).
