In 1537 Fredrick the Wise ask Martin Luther to prepare a a summary of the Lutheran teaching in preparation for a church council. The result is the Smalcald Articles. In three parts Luther discusses the Trinity and Two Natures of Jesus, the Gospel and its abuse in the church, and outlines the major articles of the faith. Together with the Small and Large Catechisms, the Smalcald Articles are included in the Book of Concord, making it one of the most important writings of the Reformer.