Paul's epistle to the Romans is one of the most beloved writings in the entire biblical canon, especially for Augustinians and Protestants. It is the subject of thousands of commentaries, many by the most important doctors of the church: Augustine, Aquinas, Luther, Calvin, Hodge, and Barth, to name a few. It offers the doctrines of sin, the gospel, and salvation in a nutshell. It is the basis for the structure of the first Protestant textbook in what later came to be categorized as systematic theology, Philip Melanchthon's Loci Communes (1521). It is a frequently-cited sourcebook of the Reformation solas, which teach that salvation comes by grace alone through faith alone because of the work of God through Christ alone. It is the site of the