In the 1950 encyclical Humani Generis, Pius XII, relying on Pius IX, makes a rather startling claim about the duty of theologians in the church:
It is also true that theologians must always return to the sources of divine revelation: for it belongs to them to point out how the doctrine of the living Teaching Authority is to be found either explicitly or implicitly in the Scriptures and in Tradition. (Humani Generis 21)
What is the primary reason “theologians must always return to the sources of divine revelation”? To show how a doctrine that has already been defined by a “living Teaching authority is to be found” there. From a Protestant perspective, of course, this rather seems to beg the question: one might have thought the first job of a theologian, or a Christian in general, would have been to determine whether a doctrine has the support of divine revelation rather than assuming from the outset that of course it does. Obviously, such a position evacuates revelation of any ability to correct and reform the church. But it does more than that: if intended to be taken seriously, it evacuates the theologian of the ability of doing honest-to-goodness historical investigation of a doctrine once the “living Teaching authority” has defined it. It assumes what ought to be proved, and makes of the theologian an ex post facto rhetorician, carrying around an assertion in search of an argument.
It is for that reason that Heiko Oberman, in his early article “Quo Vadis? Tradition from Irenaeus to Humani Generis,” gives the following gloss: “The task of the doctor, be he biblical scholar or Church historian, is to read the latest doctrinal decisions back into his sources” (251). Such a procedure has a couple of effects. First, it places (in the words of Thomas Sartory, whom Oberman quotes) the “‘teaching office of the Church…more strongly…in the realm of irrational faith'” (ibid.). (The charge is not, I think, meant to be overtly polemical; Sartory was, after all, a Benedictine monk and Roman Catholic theologian, albeit one who was very sympathetic to Martin Luther.) Why? Because it places dogmatic definitions outside of the evidential scrutiny of revelation (whether of Scripture or of tradition, in the terms of the concept of revelation employed in Humani Generis). If one is already assured of what one will find– indeed, if one must find the already-defined result– then evidence is superfluous. Traditionally, one might say that what counts as “evidence” in the realm of dogma is revelation. But what need does one have of it if one already knows what the dogma is and must be anyway? This is the essence of irrationalism, which is to say, fideism: evidence has no demonstrative role to play.
Second, given that “revelation” includes tradition in this document, the perspective voiced by Pius XII is going to have a profound impact on the study of history as well, for it too must be denuded of any critical or objective component when a question of dogma is at stake. In other words, it must cease to be genuine historical study. Thus Oberman comments that “[t]he ‘secular’ codes of historical inquiry will retain an importance for the Protestant theologian which it has not for his Roman Catholic colleague” (252). (Note, again, that this is not a generalization regarding all historical inquiry: it is a statement about what must necessarily follow once the “living Teaching Authority” has defined a dogma.) History becomes merely apologetics, and so he comments on a recent work by Peter Lengsfeld that his “study on tradition is an example of this new apologetic task of the doctor which should not be confused with historical inquiry” (252, n.1).
It is important to understand why he calls the type of investigation described above as apology rather than historical inquiry. As Oberman writes:
Especially due to the mariological dogmas of 1854 and 1950, theologians have concluded once again, that not only Scripture, but now also Scripture and tradition taken together are materially insufficient to support by simple explication these authoritative definitions. Scripture and tradition are still held to be the sources, and the Teaching office of the Church, the norm which preserves and interprets the sources. But in as much as this interpretation is synthetic, the norm takes on the function of the source. The Apostolic Constitution in which the bodily assumption of the Virgin Mary is defined refers to the unique consensus, not of the Church of all ages, but of the present-day Church. Not as an argument for, but as part of this authoritative definition it is announced that this divine truth is contained in the deposit of faith. (253; underlining represents original emphasis; bold is my emphasis)
The last sentence is the crucial one. A dogma is not recognized to be such because an argument can be brought forward from the deposit of faith to that effect. The claim, absent and prior to any argument, is made part of the definition itself. The theologian may then defend what is already assumed to be the case, but he does not prove the case as a necessary prerequisite for believing the doctrine. The task is therefore apologetic.
The question of the relation between Scripture and tradition is of fundamental importance, and one must be very careful how it is formulated. If the material sufficiency of revelation no long obtains, whether explicitly or functionally, the definition of dogma becomes simply a description of what the Church happens to think at a given moment. “[I]n this last stage,” Oberman says,”…truth is grasped and held by introspection and self-analysis on the part of the Church focused in the Teaching Office” (253-4). Again, this is not intended to be flippant or sarcastic. It is what necessarily follows when doctrine is not the product of reflection on revelation.1 It is by definition incapable of being tethered to any evidentiary ground. The question of the relation between faith and reason has always been vexed, but the method described in Humani Generis 21 seems to me a perilous way to solve it.
One could say more: if Oberman is right, the proposed solution entails abandoning one half of the polarity, and for that reason is no solution at all.