The author did not like the title, but he had no control over that aspect of the book. Reggie is an African American who earned his Ph.D. at Fuller Theological Seminary. I indexed the book for him. At the Baptist church in Harlem was where Bonhoeffer was introduced to the 'suffering Jesus' and how an oppressed people respond to Him. This turned Bonhoeffer's theology, seemingly, 180 degrees. The book, The Cost of Discipleship, was published in 1937. I believe Bonhoeffer's statement "Salvation is free, but discipleship will cost you your life." When he wrote that I do not know if he was thinking of our physical life or our personal, selfish life. I tend to think the latter. For Bonhoeffer it turned out to be both, personal and physical life.
Another line that shook me and influenced my life is:
Only he who believes is obedient and only he who is obedient believes.