This book discusses a fundamental lesson facing a servant of Christ—the breaking of the outer man by the Lord for the release of the spirit. The only work God approves is that of the spirit, and the breaking of the outer man is the only way that the spirit can have full freedom. All of these messages were given by Watchman Nee during his training in Kuling for his co-workers in 1948 and 1949. May the Lord bless the readers through these pages.