Yahrtzeit of Rabbi Chaim of Volozhin (1749-1821), the most prominent student of the Vilna Gaon. Rav Chaim established the Volozhin yeshiva in 1803, which was Judaism's main Talmudic study center throughout the 19th century, with tens of thousands of students passing through its doors. The Volozhin yeshiva remains the model of yeshivas today. Rav Chaim's most famous work was Nefesh HaChaim, a kabbalistic work which emphasizes the importance of Torah study and mitzvah observance for coming close to God. He also authored Ruach Chaim and Nishmat Chaim.