Seventeen previously published papers, here updated and revised, and one hitherto unpublished esssay explore the medieval notion of the Seven Deadly Sins and several aspects of medieval sermons. These scholarly studies examine how the commonplace of seven "chief vices" was analyzed in scholastic theology and used in preaching and in hearing confession. The influence of one major Summa de vitiis on other works of its kind is investigated in some detail. In the field of medieval preaching, the author examines sermon collections, academic speech acts, sermons for saints, and preachers' use of proverbs in French. Several works by English Dominican authors, particularly Fishacre, Bromyard, Holcot, and an ars praedicandi, are brought to light. The essays are based on fresh investigation of medieval manuscripts and accompanied by critical editions of the relevant texts.