Religion of Fear reveals the story of how a Pentecostal sect, the Church of God of the Union Assembly, a small splinter group of the holiness Church of God movement, evolved into one of the largest and wealthiest cults in America. At its height in 1995, the Union Assembly included fifty-four churches spread across nineteen states. Spanning nearly a hundred years and three generations of family leadership and relying on hundreds of interviews with members and former members, David Cady's groundbreaking investigation begins, in 1917, with the Church's illiterate but magnetic founder, Charlie (C. T.) Pratt, summoning a congregation of resilient followers with little more than a flair for spectacle. As power dynamics stir within the maturing Church, Cady turns to C. T.'s fourth son, Jesse, who conspires to wrest the Union Assembly from his five brothers and dismiss his own parents from the church they had created. Jesse dominated the Church with fear and a demand of total obedience from its nearly 15,000 members until his mysterious death at age fifty-six.

As Cady reveals, this event triggered a succession crisis in the Pratt-family ranks as Jesse's wife fostered her son Jesse Junior's rise to power and spurned other heirs presumptive to the Church. Jesse Junior turned out to be a tormented leader who drove his followers to the brink of poverty with an uncompromising demand that they give their all to God-and to him. The church's fortune squandered and its future under threat, Jesse Junior's mother was finally forced to have her favored son removed and defrocked. For all its troubling twists and turns, Cady's chronicle ends with a minor miracle, as Jesse's younger brother, Charlie T. Pratt III, takes over leadership and manages to expel the oppressive air of authoritarianism from the body of the Church and hold the community together in the process.