This bilingual edition of the Synopsis Purioris Theologiae (1625) provides English readers access to an influential textbook of Reformed Orthodoxy. Composed by four professors at the University of Leiden (Johannes Polyander, Andreas Rivetus, Antonius Walaeus, and Anthonius Thysius), it offers a presentation of Reformed theology as it was conceived in the first decades of the seventeenth century. From a decidedly Reformed perspective, the Christian doctrine is defined in contrast with alternative or diverging views, such as those of Roman Catholics, Arminians, and Socinians. The Synopsis responds to challenges coming from the immediate theological, social, and philosophical contexts. The disputations in this the third volume cover such topics as the sacraments, church discipline, the role of civil authorities, and eschatology. This volume also presents a thorough historical and theological introduction to the whole of the Synopsis.