Obama is a Protestant Christian whose religious views developed in his adult life. He wrote in The Audacity of Hope that he "was not raised in a religious household." He described his mother, raised by non-religious parents, as being detached from religion, yet "in many ways the most spiritually awakened person... I have ever known", and "a lonely witness for secular humanism." He described his father as a "confirmed atheist" by the time his parents met, and his stepfather as "a man who saw religion as not particularly useful." Obama explained how, through working with black churches as a community organizer while in his twenties, he came to understand "the power of the African-American religious tradition to spur social change."