Theodore Parker was one of the most controversial theologians and social activists in pre-Civil-War America. A vocal critic, of traditional Christian thought and a militant opponent of American slavery, he led a huge congregation of religious dissenters in the very heart of Boston, Massachusetts, during the 1840s and 1850s. This book argues that Parker's radical vision and contemporary appeal stemmed from his-abiding faith in the human conscience and in the principles of the American revolutionary tradition. A leading figure in Boston's resistance to the Fugitive Slave Law, Parker became a key supporter of John Brown's dramatic but ill-fated raid on Harper's Ferry in 1859. Propelled by a revolutionary conscience, Theodore Parker stood out as one of the most fearless religious reformers and social activists of his generation.