This volume is a classic appeal for true holiness and purity of heart by a master in the spiritual life, and it is for all those in every generation who hunger and thirst after righteousness. In this revised Legacy Edition of Dr. A. B. Simpson’s widely accepted work on sanctification, the emphasis remains upon the possibility of each believer’s experiencing perfect love through perfect faith and union with the Lord Jesus Christ. Dr. Simpson experienced and taught that “herein is our love made perfect…because as he is, so are we in this world” (I John 4:17), and that the full reception of our oneness with Jesus gives us perfect love. Dr. Simpson’s unique ministries to the body of Christ began well over a century ago. He served pastorates in Canada, Kentucky, and New York before founding The Christian and Missionary Alliance in 1887. The warmth and vigor of his preaching, teaching, and writing still come sharply into focus through his books, hymns, and messages long after his death in 1919.