Christian truth as unchanging reality

I finally come to the second of five implications of the patristic conception of the regula fidei (or regula veritatis) for dogmatics. The first implication - that Christian faith constitutes a unity - I outlined here. The source is Hägglund's "Die Bedeutung der >Regula Fidei<Studia Theologica 12 1958:1-44.

If the oldest form of Christianity reckoned with a regula fidei, then it presupposed that the content of faith from the beginning on was fixed and forever unchanging. As we have seen, this does not mean that the church fathers sanctioned a specific doctrinal axiom. Although the scriptures of the prophets and apostles were normative—and according to a later terminology “canonical”—, they nevertheless functioned as regula only because they they were the original and only authentic witnesses to the salvific events. The unalterability of the faith consists in the fact that these events as facts of past history simply cannot be changed.

The possibility of a “development” of Christian doctrine exists only in the sense that the presentations of the doctrinal content change and, with more or less completeness, is carried out via new methods or through different teachers in different situations. The content of faith itself, the regula fidei, remains unchanged, for the revelatory event itself can be as little changed as historical facts themselves.