Henry Bullinger was one of the most widely esteemed leaders of the Reformation Churches. The Decades was the most famous of the 150 treatises and manuscripts that he wrote, deriving its name from being a series of fifty theological addresses divided into five groups of ten. Each address is a helpful, detailed exposition of an important doctrine. Combined, they provide an overview of the Christian faith suitable for the everyday Christian. When first published The Decades outsold Calvin's Institutes in England, a work that performs a similar function. This edition features introductions to the life of Bullinger and to the work itself by George Ella and Joel R. Beeke.