Luther’s liturgical reform was guided by the principle that if the Scriptures did not expressly reject a particular practice, the church was free to keep it. Consequently, Lutheran worship retained much of the ceremonial practice of Catholic worship.
There are a number of reasons for considering the Lutheran tradition as the most conservative of the Protestant traditions of worship. Martin Luther (1483–1546) had high respect for the existing Christian cultus; his inclination was to purge those aspects that could not be reconciled to his theology and to retain the rest. He could be quite radical on occasion (as with the canon of the Mass) but on the whole, retained more than he rejected. He tended to move carefully; others anticipated him on vernacular liturgies.
After statements in The Babylonian Captivity (1520) that were to be determinative for almost all subsequent Protestant sacramental theology, Luther moved to liturgical reform with vernacular baptismal rites in 1523 and 1526. The same years also saw new eucharistic rites, the Formula Missae (in Latin) and German Mass. Later years saw forms for marriage, ordination, and penance. In general, existing practices endured, but rites were conducted in the vernacular, and popular participation was promoted whenever possible.
Three emphases stand out: music, preaching, and frequent communion in both kinds. Luther considered music one of God’s greatest gifts and cultivated its use in worship through service music and hymnody. He led the way in writing hymns himself, and vigorous hymn singing has always been a hallmark of this tradition. Luther’s insistence that preaching be a part of all congregational worship contributed to a rebirth of preaching. He also encouraged all the laity who were properly prepared to receive the bread and wine at each Eucharist.
As for vestments, images, and much of the medieval cultus that was theologically neutral, Luther allowed their continuance; they came to be known as adiaphora or things indifferent. Thus much more survived in Lutheran countries, especially in Sweden and Finland, where Lutheran worship remained its most conservative, than in other Protestant countries. Yet even this is relative. Recent studies have shown just how much survived during the long period of Lutheran orthodoxy. In Bach’s Leipzig, there were daily public prayers, a weekly Eucharist with a great many communicants, and a rich observance of the church year. Although the services were in German, one gets the feeling that not all that much had changed from the Middle Ages in two hundred years of Lutheranism.
The real change came not with the Reformation but with the Enlightenment. Daily services in Leipzig ended in the 1790s and much of the continuing medieval cultus vanished in the face of rationalism, even in the Church of Sweden. Much of this has been blamed on the influence of the Reformed tradition, but more is probably due to the spirit of the age. The nineteenth-century saw a gradual reaction to the Enlightenment with an attempt to recover early Lutheran worship. In Germany, Wilhelm Loehe (1810–1895), in Denmark, Nikolai Grundtvig (1783–1872), and various other leaders elsewhere sought a return to Lutheran orthodoxy and orthopraxis. The indication of their success is successive revisions of various service books and hymns. More recent versions, especially the American Lutheran Book of Worship (1978), have moved into the ecumenical mainstream while retaining a Lutheran character, especially in the emphasis on music.