Excursus on Confessional Authority
An observation: when ordained to serve the ELCA, a new pastor has to promise to teach and preach according to the Lutheran confessions. This means the whole Book of Concord. Does this mean that the pastor is now bound to respect as equals the Augsburg Confession and the Formula of Concord? Not exactly. My German forebears are now turning over in their graves but my Danish relatives leap for Joy.
When the Reformation spread to other countries, including Denmark in Luther's lifetime, the main tool used was the Augsburg Confession. The Danes and eventually the Norwegians also took on the Small Catechism. After all, you have a formal document for public use and then the catechism to teach the faith. I don't know the situation in Sweden or in Finland.
This arrangement in confessional documents extended to many of the immigrant churches in the United States. When asked to list their confessional documents some Lutherans would say: "Augsburg and the Catechism," others would say: "Augsburg, its Apology, and the Catechism," while some would insist until blue in the face: "the whole Book of Concord." The latter would make fellowship dependent upon the whole Book of Concord, and that is the situation, at least in the letter, that we find ourselves in the ELCA, at least on paper.
Early in this interchange between this various Lutheran parties in the United States there emerged another problem: do I subscribe to the Confessions because they agree with Scripture or only insofar as the agree with Scripture. The parties that held to the whole Book of Concord scheme usually landed in the former camp and others across the spectrum. This question affects which confessional documents you recognize. It is worth mentioning that the Formula of Concord begins with a statement on Scriptural authority and that it more or less says: "in the case of a shootout between the Scripture and the Confessions, the Scripture wins."
Confessional authority, like Biblical authority, is a matter that emerges in the communities that used the documents after their writing and being brought together. Thus, it is difficult to look at the German situation with its collusion between the church and the rulers who adopted the confessions as legal norms for governing the churches and see this arrangement as the evangelical norm for confessional authority. Adherence to the Augsburg Confession was the bare minimum norm for the legal existence of Lutheran territories after the Peace of Westphalia. As Karl Barth repeated numerous times, "'back to' is never a good slogan."
When professing to teach and preach in accord with the confessions it makes sense to identify a hierarchy of authorities. The Augsburg Confession first and then the Catechism, and then the rest of the Confessions with the Formula at the 'bottom.' This is respectful not only of the non-German Lutheran traditions but also the Confessions themselves.