This fascinating work by the fifth Lubavitcher Rebbe weaves together Chasidic doctrine, Kabbalah, Biblical and Talmudic texts with powerful insights into human nature. Written in the early years of the twentieth century, when the challenge of secularism and non-Jewish ideologies faced Russian Jewry, it remains a highly relevant text for study and contemplation, explaining familiar concepts and experiences in terms of spiritual truths lying beneath the surface.