Known as the Maggid ("The Voice") to Hasidic Jews, since he "voiced" the words of his master and spread the word of Hasidism over Eastern Europe.
His teachings are quoted in the volume Maggid Devarav L'Yaakov. His students included Rabbi Elimelekh of Lizhensk, Rabbi Zusha of Anipoli, Rabbi Yosef Yitzchak of Berdichev, Rabbi Shneur Zalman of Liadi and many other prominent Jewish leaders.