Vilna Gaon

Elijah ben Solomon Zalman, ( ''Rabbi Eliyahu ben Shlomo Zalman''), also known as the Vilna Gaon ( ''Der Vilner Goen''; ; or Elijah of Vilna, or by his Hebrew acronym Gra ("Gaon Rabbenu Eliyahu": "Our great teacher Elijah"; Sialiec, April 23, 1720Vilnius October 9, 1797), was a Lithuanian Jewish Talmudist, halakhist, kabbalist, and the foremost leader of misnagdic (non-hasidic) Jewry of the past few centuries. He is commonly referred to in Hebrew as ''ha-Gaon mi-Vilna'', "the genius from Vilnius".

Through his annotations and emendations of Talmudic and other texts, he became one of the most familiar and influential figures in rabbinic study since the Middle Ages. Although he is chronologically one of the ''Acharonim'', some considered him one of the ''Rishonim''

Large groups of people, including many ''yeshivas'', uphold the set of Jewish customs and rites (''minhag''), the "''minhag ha-Gra''", named after him, and which is also considered by many to be the prevailing Ashkenazi ''minhag'' in Jerusalem.

Born in Sielec in the Brest Litovsk Voivodeship (today Sialiec, Belarus), the Gaon displayed extraordinary talent while still a child. By the time he was twenty years old, rabbis were submitting their most difficult ''halakhic'' problems to him for legal rulings. He was a prolific author, writing such works as glosses on the Babylonian Talmud and ''Shulchan Aruch'' known as ''Bi'urei ha-Gra'' ("Elaborations by the Gra"), a running commentary on the Mishnah, ''Shenoth Eliyahu'' ("The Years of Elijah"), and insights on the Pentateuch entitled ''Adereth Eliyahu'' ("The Cloak of Elijah"), published by his son. Various Kabbalistic works have commentaries in his name, and he wrote commentaries on the Proverbs and other books of the Tanakh later on in his life. None of his manuscripts were published in his lifetime.

When Hasidic Judaism became influential in his native town, the Vilna Gaon joined the "opposers" or ''Misnagdim'', rabbis and heads of the Polish communities, to curb Hasidic influence.

While he advocated studying branches of secular education such as Mathematics in order to better understand rabbinic texts, he harshly condemned the study of Philosophy and Metaphysics. Provided by Wikipedia