document in Jewish thought. While personal accounts of the mystical life are rare in Judaism, in this work Rabbi Dovber guides the devotee through the many intellectual and emotional levels of Chabad meditation. It differentiates between the external emotional fervor of general Chasidism, with the Chabad ideal of inner ecstasy in prayer. It is related that Rabbi Schneur Zalman's prayers were so ecstatic that he could not contain their outer emotional expression, and without self-awareness, would roll on the floor or end up in a different location. His son Schneuri, meanwhile, would pray for hours in static ecstasy, until all his clothes would be soaked in perspiration. One of his most famous works, entitled "Sha'ar HaYichud" (The Gate of Unity), now translated to English , describes the creation and entire make-up of the world according to Kabbalah. The work begins with the "Essence of G-d," and traces the creation of the universe down to the physical world itself, using complicated parables to illustrate difficult points. The book also describes, in its first ten chapters, the proper way to meditate on these Kabbalistic ideas. List of works Maamarei Admur Ha'emtza'i - Chassidic discourses on the Torah and festivals - 20 vols. Bi'urei HaZohar - explanation of the Zohar Pirush HaMilos - Chassidic explanation of the liturgy Kuntres HaHispaalus - on meditation and ecstasy in prayer; also known as Kuntres HaHisbonenus Shaarei Teshuvah - on Teshuvah, repentance Derech Chaim - continuation of Shaarei Teshuvah Toras Chaim - Chassidic discourses on the books of Bereshis and Shemos Ateres Rosh - Chassidic discourses for the Days of Awe Shaar HaEmunah - explanation of the Mitzvah of faith and the festival of Pesach Shaar HaYichud - explanation of Seder hishtalshelus Shaarei Orah - on the festivals of Chanukah and Purim Imrei Binah - explanation of the Mitzvah of reading the Shema and donning the Tefillin Citations Books Communicating the Infinite: The Emergence of the Habad School, Naftali Loewenthal, University Of Chicago Press, 1990. Academic survey of the formation of Chabad in its first two generations, describing the divergent spiritual interpretations of DovBer Schneuri and Aharon HaLevi of Strashelye. Hasidic Prayer by Louis Jacobs. Littman Library of Jewish Civilization. New edition 1993 (Paperback). Full overview and explanation of forms of prayer across the whole Hasidic movement. Gives detailed explanation of the unique Chabad approach, and its differences from other ways. Tract on Ecstasy by Dobh Baer