Reformation and mission are not unconnected concepts. According to Luther, every single person, being a helpless sinner in the eyes of God, needs to hear God’s word as law and gospel. The church’s mission finds its source, content, and strength in the missio Dei, God’s mission to save the lost. The Christian church’s mission on earth is to preach and lend credibility to its proclamation through Christians’ witness of a new life of evangelical freedom. Church doctrine and real-life practice of one’s Christian identity converge on the mission field, that is, in Christians’ daily life of witness as they fulfil their human callings in the new freedom of evangelical faith.
It was precisely the lack of an authentic Christian piety, including gospel-aligned practice within medieval Christendom, that prompted Luther to set out on a mission to “Christianize Christendom,” beginning in Germany and extending beyond. Though Luther’s “missionary” agenda crystalized primarily during 1517–1522, he arrived at a fuller understanding of the dire state of Christianity in Germany after his Saxon visitations of 1528. His vision of a genuinely Christian church emerged as he processed the biblical witness in the light of his own monastic experience as an Augustinian friar, the legacy of selected scholastic teachers, medieval mystics and renewal movements, earlier reformers, and the ideas of 16th-century humanists, as well as a number of his contemporaries, and, above all, his colleagues in the so-called Wittenberg Circle.
Motivated by his understanding of the missio Dei, Luther’s mission was to destroy the existing rampant idolatry and superstition in its various forms and to reintroduce the theocentric message of the gospel which changes not only humans’ ideas about God and their attitudes toward Him, but also the Christian practice of piety in the areas of liturgy, the personal life of a Christian, and one’s social, political, and economic engagements. United in faith to Christ, believers are moved by the Holy Spirit away from religious schemes of merit to a theocentric, communal vision of life in true devotion, which not merely produces new obedience but entails it. Luther did not champion a one-sided internalization, spiritualization, and individualization of faith. Much of the medieval heritage could be reappropriated in the renewed Christian faith and practice, provided the old forms were conducive to evangelical teaching.
Luther realized that the Holy Spirit’s work of regeneration in Christians will never be complete in this life, just as the mission of the gospel will not achieve the conversion of all. Instead, “real Christians” are to live in repentance, ever renewed in faith, hope, and love as they patiently bear the cross of suffering. While never losing hope in the final victory of God over the forces of the devil, Christians must accept that they will always be a minority, constantly under attack by the evil one. Persecution may help the church to live and spread the gospel. In what Luther considered to be the final stage before the imminent apocalyptic closure of history, the newly Christianized, evangelical church must use all its resources for the sake of faithful proclamation of the gospel—even to Jews, Turks, and newly discovered territories (though these emphases are rather marginal in Luther). For this to happen, new preachers and teachers need to be trained and new evangelical schools must be established, which is the duty and responsibility of Christian landlords and magistrates. Christian liturgy and preaching, evangelical catechesis, the singing of Christian hymns, the spreading of Reformation pamphlets and woodcut engravings, Christian art, architecture, and prayer are all effective missionary tools at the church’s disposal.
An acute sense of apocalyptic urgency stimulated in Luther not only a highly focused, disciplined, courageous stance and action, and a strong prophetic self-perception, but also impatience with his opponents, which resulted in some inexcusable statements against Jews, “papists,” Anabaptists, and other dissenting groups of his time. While Luther’s agenda of Christianization took root almost exclusively in Germany and Scandinavia, his effort to reinvent an evangelical (i.e., theocentric, gospel-oriented) piety found its new expression in later pietistic renewal movements (among Lutherans, Moravian Brethren, and Methodists), thereby influencing, though indirectly, global Christianity and mission.