A Voice of Warning is a lively and passionate nineteenth-century argument for Mormonism. Written by Parley P. Pratt, one of the most colorful personalities in the early history of the Church of Jesus Christ of Latter-day Saints, it was also Mormonism's most important noncanonical book for more than half a century after its original publication in 1837. Pratt presented the case for Mormonism by an appeal to history, reason, and scores of passages from the Bible. Its animated, argumentative, and very often clever style explains Mormonism well and draws a line between it and conventional Christianity.