The reformers’ early preoccupation with marriage was driven, in part, by their jurisprudence. The starting assumption of the budding Lutheran theories of law, society, and politics was that the earthly kingdom was governed by the three natural estates of household, Church, and state. Hausvater, Gottesvater, and Landesvater; paterfamilias, patertheologicus, and patapofiticus— these were the three natural offices through which God revealed Himself and reflected His authority in the world. These three offices and orders stood equal before God and before each other. Each was called to discharge essential tasks in the earthly kingdom without impediment or interference from the other. The reform of marriage, therefore, was as important as the reform of the Church and the state. Indeed, marital reform was even more urgent, for the marital household was, in the reformers’ view, the “oldest,” “most primal,” and “most essential” of the three estates, yet the most deprecated and subordinated of the three. Marriage is the “mother of all earthly laws,” Luther wrote, and the source from which the Church, the state, and other earthly institutions flowed. “God has most richly blessed this estate above all others, and in addition, has bestowed on it and wrapped up in it everything in the world, to the end that this estate might be well and richly provided for. Married life therefore is no jest or presumption; it is an excellent thing and a matter of divine seriousness.”
The reformers’ early preoccupation with marriage was driven, in part, by their politics. A number of early leaders of the Reformation faced aggressive prosecution by the Catholic Church and its political allies for violation of the canon law of marriage and celibacy. Among the earliest Protestant leaders were ex-priests and ex-monastics who had forsaken their orders and vows, and often married shortly thereafter. Indeed, one of the acts of solidarity with the new Protestant cause was to marry or divorce in open violation of the canon law and in defiance of a bishop’s instructions. This was not just an instance of crime and disobedience. It was an outright scandal, particularly when an ex-monk such as Brother Martin Luther married an ex-nun such as Sister Katherine von Bora —a prima facie case of spiritual incest As Catholic Church courts began to prosecute these canon law offenses, Protestant theologians and jurists rose to the defense of their co-religionists, producing a welter of briefs, letters, sermons, and pamphlets that denounced traditional norms and pronounced a new theology of marriage.
Evangelical theologians treated marriage not as a sacramental institution of the heavenly kingdom, but as a social estate of the earthly kingdom. Marriage was a natural institution that served the goods and goals of mutual love and support of husband and wife, procreation and nurture of children, and mutual protection of spouses from sexual sin. All adults, preachers and others alike, should pursue the calling of marriage, for all were in need of the comforts of marital love and of protection from sexual sin. When properly structured and governed, the marital household served as a model of authority charity, and pedagogy in the earthly kingdom and as a vital instrument for the reform of Church, state, and society. Parents served as “bishops” to their children. Siblings served as priests to each other. The household altogether — particularly the Christian household of the married minister — was a source of “evangelical impulses” in society.
Though divinely created and spiritually edifying, however, marriage and the family remained a social estate of the earthly kingdom. All parties could partake of this institution, regardless of their faith. Though subject to divine law and clerical counseling, marriage and family life came within the ,jurisdiction of the magistrate, not the cleric; of the civil law, not the canon law. The magistrate, as God’s vice-regent of the earthly kingdom, was to set the laws for marriage formation, maintenance, and dissolution; child custody, care, and control; family property, inheritance, and commerce.
Political leaders rapidly translated this new Protestant gospel into civil law. Just as the civil act of marriage often came to signal a person’s conversion to Protestantism, so the Civil Marriage Act came to symbolize a political community’s acceptance of the new Evangelical theology. Political leaders were quick to establish comprehensive new marriage laws for their polities, sometimes building on late medieval civil laws that had already controlled some aspects of this institution. The first reformation ordinances on marriage and family life were promulgated in 1522. More than sixty such laws were on the books by the time of Luther’s death in 1546. The number of new marriage laws more than doubled again in the second half of the sixteenth century in Evangelical portions of Germany. Collectively, these new Evangelical marriage laws: (1) shifted primary marital jurisdiction from the Church to the state; (2) strongly encouraged the marriage of clergy; (3) denied that celibacy, virginity, and monasticism were superior callings to marriage; (4) denied the sacramentality of marriage and the religious tests and impediments traditionally imposed on its participants; (5) modified the doctrine of consent to betrothal and marriage, and required the participation of parents, peers, priests, and political officials in the process of marriage formation; (6) sharply curtailed the number of impediments to betrothal and putative marriages; and (7) introduced divorce, in the modern sense, on proof of adultery, malicious desertion, and other faults, with a subsequent right to remarriage at least for the innocent party. These changes eventually brought profound and permanent change to the life, lore, and law of marriage in Evangelical Germany.
John Witte, Jr., Law and Protestantism: The Legal Teachings of the Lutheran Reformation (Cambridge, United Kingdom: Cambridge University Press, 2002), 200-202.