First published in 1819, this classic Chasidic text, by the second leader of Chabad-Lubavitch, Rabbi DovBer, explores the world of the "Service of the Heart," focusing on prayer and repentance.

The Lubavitcher Rebbe would often suggest the studying of this text during the days of the month of Elul and of the New Year - days of introspection and renewal. For this edition, the entire volume has been reset in an aesthetically clear font, and numerous corrections have been made.