Simcha Bunim Bonhardt of Peshischa (Yiddish: שמחה בונם בונהרט פון פשיסכע, [ˈsɪmχə ˈbʊnɪm ˈbʊnhaʁt ˈfʊn ˈpʒɪ'sχə]; c. 1765 – September 4, 1827) also known as the Rebbe Reb Bunim was the second Grand Rabbi of Peshischa (Przysucha, Poland) as well as one of the key leaders of Hasidic Judaism in Poland. The main disciple of R. Yaakov Yitzchak Rabinowicz ("the Yid Ha-Kadosh"), from 1813 to 1827, he led the Peshischa movement of Hasidic thought, in which he revolutionized 19th-century Hasidic philosophy by juxtaposing the rationalistic pietism of German-Jewry with the spiritual nature of God defined by the Hasidic movement.