Aharon Perlow of Koidanov

Aharon Perlow (; 1839–1897) was the third Rebbe of the Koidanov Hasidic dynasty. He was a charismatic leader who attracted thousands of followers and effected a revival of the Koidanover dynasty founded by his grandfather, Rabbi Shlomo Chaim Perlow (1797-1862). He authored several important works that became standard texts for Koidanover Hasidim to this day, including a siddur, Seder Tefilot Yisrael Or Hayashar ("The Direct Light: Order of Prayers of Israel").

Biography Perlow was born in Koidanov (present-day Dzyarzhynsk, Belarus) to Rabbi Baruch Mordechai Perlow (1818–1870), the second Koidanover Rebbe. He was the great-great-grandson of both Rabbi Mordechai of Lyakhavichy (Lechovitch) (c. 1742–1810) and Rabbi Asher Perlow of Karlin. He became the third Koidanover Rebbe upon the death of his father in 1870.

The new rebbe's charismatic personality and scholarship attracted thousands of Hasidim to Koidanov.

In his writings and demeanor, Rebbe Aharon embodied the "mystical-charismatic style" of the Rebbes of Karlin-Stolin, of which Koidanov is a branch. He also authored a siddur entitled Seder Tefilot Yisrael Or Hayashar ("The Direct Light: Order of Prayers of Israel"), in which he enumerated "eight mystical practices for spiritual perfection". This siddur is still used by Koidanover Hasidim today.