This Article explores the surprising use of medieval Catholic canon law in the new Protestant civil law of Lutheran Germany within a decade of Luther's decision to burn the canon law books and reject papal authority. Inertia is part of the reason. Prior to the Reformation, the canon law was a vital part of the ius commune in which most jurists and theologians who had joined the Reformation cause were trained. In the heady days of revolutionary defiance of Pope and Emperor in the 1520s, it was easy for Protestant neophytes to be swept up in the radical cause of eradicating the canon law and establishing a new evangelical order based on the Bible alone. When this revolutionary plan proved unworkable, however, theologians and jurists invariably returned to a truncated version of the canon law and civil law that they knew. Innovation is also part of the reason. Lutheran theologians after 1530 offered an innovative theory of the church that ultimately required church and state officials to use both biblical and canonical rules and procedures to govern the polity, property, and clergy of the church. Lutheran jurists offered an innovative theory of the state and the sources of civil law that ultimately saw much of the canon law as a quintessentially Christian and equitable law that could be readily used in Lutheran lands, especially in the governance marriage and family, education and schooling, charity and welfare.
Witte, Jr., John (2000) studied this question.