In his new book, Norman Simms re-defines the study of two often misunderstood religious groups. The first are Marranos who claim descent from the persecuted Spanish Jews forced to convert to Catholicism, yet who nevertheless continued to practice Jewish rituals secretly. The other group consists of the Penitentes, a Catholic group accused of violent acts of self-flagellation and other forms of masochism. Examining both groups through rabbinics, literature, psychology, and anthropology, Simms brings his readers to a new understanding of both these religious groups as well as religious mentalities.