This book presents the backstory of how the Catholic Church came to clarify and embrace the role of Israel in salvation history, at the behest of an unlikely personality: Jules Isaac. This embrace put to an end the tradition, more than fifteen centuries old, of anti-Jewish rhetoric that had served as taproot to racial varieties of anti-Semitism. Prior to Isaac's thought and activism, this contemptuous tradition had never been denounced in so compelling a manner that the Church was forced to address it. It is a story of loss and triumph, and ultimately, unlikely partnership.

Isaac devoted his years after World War II to a crusade for scriptural truth and rectification of Christian teaching regarding Jews and Judaism. Isaac's crusade culminated in an unpublicized audience with Pope John XXIII-a meeting that moved the pope to make a last-minute addition to the Second Vatican Council agenda and set in motion the events leading to a revolution in Catholic teaching about Jews.