"The North and the South were in antagonism and slavery was a burning question, although the great Civil War was not to come for some years yet. Charles Haddon Spurgeon, in the course of his sermons, felt bound to pass strictures [moral criticism] upon the whole system of slavery, and at once the sale of his sermons in the Southern States fell almost to nothing, while scores of insulting and threatening letters were sent to the preacher."
Charles Ray in A Marvelous Ministry: The Story of C.H. Spurgeon's Sermons: 1855-1905. Forest Gates, Essex. 1905. p.13