Mattias Joseph Scheeben‘s The Mysteries of Christianity begins with a reflection on the nature of Christian mystery. It can also be read as a commentary on the prooemium to the Summa contra Gentiles Book IV (which is itself an echo of the prooemium to the work as a whole, SCG I.1–8). At key points—either by design or by the natural contours of the truth of the subject—it even seems to follow Aquinas’ text. For instance, Aquinas spends time to clarify the limits of human knowledge even of the essences of natural things, as does Scheeben in the first pages of his book, and in no sparing detail.
He also frames the context of the theological contemplation of the mysteries of the faith in similar terms. On the one hand, Scheeben argues against a type of “mystery-fideism” which would curtail even the truths about God that human reason is able to discover. Thus, he says:
Thus, for example, [one theologian] maintains that without a knowledge of the Trinity in God we can have no true notion of God at all, and consequently that any teaching about God is true only in terms of a mystery that comes to our knowledge through revelation. We can admit neither of these propositions, the first if only for the reason that the second would thereupon follow. In the second proposition we discern a decided encroachment on reason in its own realm, and in the first a confusion between a false notion and a one-sided, inadequate notion. (pp. 15–16)
On the other hand, the truth of mystery exceeds our natural capacities. Scheeben’s definition of Christian mystery—as opposed to a broader sense of “mystery” that could include even the naturally unknown—is as follows: “Christian mystery is a truth communicated to us by Christian revelation, a truth to which we cannot attain by our unaided reason, and which, even after we have attained to it by faith, we cannot adequately represent with our rational concepts.” (p. 13) Thus, the essence of Christian mystery contains two necessary and sufficient conditions: “First, that the existence of the proposed truth is attainable by no natural means of cognition, that it lies beyond the range of the created intellect; secondly, that its content is capable of apprehension only by analogous concepts.” (p. 11) The central mysteries of Christianity possess their own sublime light, and
the light derived from the consideration of each separate mystery spreads automatically far and wide over the inner relationship and the wonderful harmony pervading them all, and thus the individual pictures take their places in an orderly gallery, which comprises everything magnificent and sublime that theology possesses far in excess of all the other sciences, including even philosophy. (p. 21)
This division is also reflected in St. Thomas’ prooemium to SCG IV. There, St. Thomas distinguishes between three sorts of knowledge of divine things: what we can attain “going up” through natural reason, what must “come down” to us by revelation, and, lastly, what we hope to see of God when elevated to direct contemplation of Him. For this threefold division, Aquinas turns to Job 26:14: “Lo, these things are said in part of His ways: and seeing we have heard scarce a little drop of His word, who shall be able to behold the thunder of His greatness?” That “scarce a little drop of His word” calls to mind St. Thomas’ gloss on John 21:25 (see n. 2660): “This is because even an infinite number of human words cannot equal one word of God.”
Aquinas’ division of the ascent to, descent of, and elevation to Divine truth also unfolds from his understanding of the order of causality in the cosmos, for he uses that idea as a foundation to initiate our grasp of the threefold divine truth. He does this by beginning from our perspective, our vantage point as the ones aiming at and desiring to know God. The counterpoint, the contrasting vision to the ascent is the descent from God (see the prooemium, nn. 1–5).
The vision of the cosmos in the background of Aquinas—a cosmos awaiting faith—is answered by the cosmos of Christian mysteries, or so says Scheeben. The natural cosmos is our “ascent” to the divine, but the supernatural cosmos of mystery “descends” in revelation to us; the lower vantage meets a higher perspective arising from within what appears to it to be the divine darkness. This is where the science of theology, sacra doctrina, is found.
[So when I say that Christianity as a whole is mysterious, and is a single vast mystery, I do not mean that everything in Christianity is a mystery, but only that the higher and nobler part of it, that part which renders it specifically distinct from every other system of religious truths, even from true and uncontaminated natural religion, is mysterious and a mystery throughout; in the same way as we should say that man, although visible in body, is invisible in his essential form, his soul. (p. 15
We trust that we shall be able to bring together the mysteries of Christianity into an independent, well-ordered system in which they will appear to be a great, mystic cosmos erected, out of the depth of the divinity, upon the world of nature which is visible only to the mind. Lastly, we believe that for the scientific understanding of Christianity, for theology, nothing is more important and rich in blessings, and today in particular nothing is more seasonable, than this specialized and systematic treatment of the doctrine of mysteries.
There is in our day a pronounced tendency toward the strict separation of the various branches of knowledge. The supposition is that each science will come to full and distinct self-consciousness if it is studies in its opposition to other sciences. But how can theology build up a science of its own, and especially how can it detach itself objectively from philosophy, unless it becomes conscious of its own proper domain in which alone it is at home, and into which philosophy cannot follow? And where is its most proper domain situated if not in its doctrine of mysteries? (p. 18)]
It is a cosmos of mysteries because all other Christian mysteries are “reduced” to these nine (re + ducere, to lead back to; the nine which Scheeben writes about are the Trinity, Original Creation, Sin, the Incarnation, the Eucharist, the Church, Justification, Glorification, and Predestination). And these nine all, of course, descend from the first, the Summit of Christian mystery to which we hope one day to be elevated such that there “Nor will one perceive some measure of the divine mysteries: the divine majesty itself will be seen and all the perfection of goods.” (St. Thomas, SCG, IV.8)