"The Profits of Religion, Fifth Edition" by Upton Sinclair is a nonfiction book first published in 1917. The muckraking journalist launches a fierce attack on institutionalized religion in America, calling it a "source of income to parasites" and ally of oppression. Sinclair examines various religious establishments—from Episcopal elites to Catholic parishes to Protestant merchants to California cults—arguing they've betrayed Jesus's true message. Part of his "Dead Hand" series critiquing American institutions, the book was largely boycotted by mainstream press upon release. (This is an automatically generated summary.)
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