What separates Catholics from Protestants? The traditional answer is doctrine. Catholics and Protestants believe different teachings. But since the rise of historicism in the nineteenth century and ecumenism in the twentieth, the question of what separates the two sides has become more complicated. Doctrines are not only distinct teachings but also complicated communal expressions arising in particular contexts that may be interpreted, despite their differences, as authentic and variable symbols for time and place. Thus, the philosopher G. W. F. Hegel (a Lutheran) argued that the Roman Mass was a valid “representation” in the Middle Ages of the fundamental Christian “idea” of the Incarnation. Lutherans and other Protestants may reject the Mass, but the Mass, said Hegel, is true in its own way and is thus a valid insight into the fundamental mysteries of Christian faith (Christian Religion: Lectures on the Philosophy of Religion, ed. and trans. Peter C. Hodgson, part 3, The Revelatory, Consummate, Absolute Religion [Scholars, 1979], 256–276). Much of contemporary ecumenism has followed this Hegelian insight by focusing on the notion that rapprochement between Catholics and Protestants may be accomplished through an expansive interpretation of the liturgical components of the Mass.

Are there differences between Catholics and Protestants that go even deeper than doctrine? Friedrich Schleiermacher asserted that the social teachings of religious organizations are such differences and thus more fundamental than arguments of dogmatic theology. They center on this contrast: Catholicism, Schleiermacher claims, places the church between the individual and Christ whereas Protestantism declares that Christ and the individual are in direct relationship apart from, and often in conflict with, ecclesiastical mediation (Christian Faith, chap. 2, par. 24). Every Christian is “priest, pope, and king’” proclaimed Luther in 1520; the church is an “unequal society” in which the only right of the “multitude” is “to be led” said Pius X in 1906. This is a difference indeed.

This focus on social teachings has borne much fruit. The seminal work of Ernst Troeltsch, which is a variation of Schleiermacher's argument, is the first to come to mind. Concentrating on social teaching places traditional doctrine in the context of historical practice. Doctrinally, what we are dealing with is the contrast of fides explicate and fides implicita. Protestants of whatever stripe teach “explicit faith”: the responsibility of the individual Christian to know the content of the faith. This is borne out historically by the Protestant commitment to literacy, the vernacular Bible, and lay leadership. Catholics, on the other hand, teach implicit faith: the duty of the laity to obey the priest; thus, historically, the constant emphasis in Catholicism in each age and across cultures is on ritual practice and clerical control.

It is here where I see the contribution of Katherine Mahon. Every individual Christian, no matter his or her confessional allegiance, is required to know and reflect on the Lord's Prayer. The Lord's Prayer has been a matter of liturgical repetition, devotional meditation, and catechetical reflection from the beginning of the faith. It follows Jesus's command in Matt. 6.9: “This is how you should pray: Our Father . . .” The Lord's Prayer is thus a fundamental obligation of explicit faith for the individual Christian, whether Catholic or Protestant. It is legitimately—indeed automatically—a subject for ecumenical theology, especially as relates to Christian worship. Mahon traces the use of the Lord's Prayer in sixteenth-century reform for both Catholics and Protestants against the backdrop of its use in the Middle Ages. Both groups struggled with the inadequacies of knowledge on the part of the laity. Luther is famous (and notorious) for labeling the laity “pigs and irrational beasts” in his preface to the Small Catechism. Catholics and Anglicans faced the same problems and were as concerned as Luther over the state of knowledge about the content of faith. In the upheaval of the sixteenth century, the effort to improve the state of knowledge was pursued by all. Mahon rightly observes: “Roman Catholic catechisms from the Council of Trent and following are as much indebted to humanistic educational influence as their Protestant counterparts” (69). Katherine Mahon makes her case well. Her study is rich in detail, careful and balanced in judgment.