Overview of argument:
Archetypal theology: eternal pattern for perfect truth of supernatural revelation (Muller 234).
Ectypal theology: category inclusive of all forms of finite theology. It is formed on the basis of the archetype by a communication of grace from Creator to creature (235).
Muller ties these two categories in with Christology, following the Reformed and anti-Lutheran finiti non capax infiniti: the human nature of Jesus cannot fully share with the divine nature, which, reasoning analogously, means that the theologia unionis must be ectypal, not archetypal (250).
At this point one must step back and appreciate what Muller has done. He’s tied in epistemology with Christology almost effortlessly. He has taken the hypostatic union and shown how it forms the epistemological principle of Reformed thought—the ectypal theology (251).
“double truth” does not mean one truth is opposed to another, but that one truth may transcend another (387).
“Reason” has an instrumental function for truth (399). For example, “In a syllogism the foundation for all argument is the middle term, the common ground shared by major and minor propositions. In theology the middle term is not taken from reason, but Scripture” (403).
The “principia” of theology is its first principle(s). It must be of a higher degree than that of the conclusions drawn from it (431).
Principle of being (principia essendi): it is the principle of foundation
Principle of knowing (principia cognescendi): it is the principle of knowing
The archetype and the arche must be identical. The connection between archetype and ectypal theology is the logos prophorikos, the Word sent forth (433).
Archetypal knowledge is the principium essendi
When the archetype reveals himself, it is the principium cognoscendi.
All true theology reflects the archetype, which can only be known through a self-revelation.