The genius of Thomas Aquinas was not his introduction of new philosophical ideas or distinctions. The distinctions between essence and existence, potency and act, form and matter, the language of participation and divine ideas, even the scholastic method itself, were not his inventions. He borrowed all these from his predecessors. And yet Aquinas was not a mere eclectic. In spite of his adaptation of the ideas of Aristotle, Plato, Pseudo-Dionysius, Augustine, Ibn Sina, Maimonides, etc., Aquinas was not an amateur assimilator who pulled together a hodgepodge philosophy from the bits and pieces he had managed to forage from better thinkers.
Aquinas’s genius lay in his ability as a synthetic thinker. His unique contribution was the re-molding of a non-Christian philosophical tradition so that it looked as if it had never been anything but Christian. The Swiss theologian Karl Barth raised the hackles of philosophical theologians a generation ago by insisting that the knowledge of creation is not a matter of natural theology—that the first article of the creed is as much a matter of faith and revelation as is the second article. Natural reason is not able to say “I believe in God the Creator.” In the previous pages I have tried to show that essentially Aquinas would have agreed with Barth. Theology cannot prove the articles of faith. There is no reason, however, why theology cannot use the tools of philosophy to come to a better understanding of those articles that it cannot prove.
It was the Christian doctrine of creation that provided St. Thomas with the framework to articulate theologically his understanding of the relation between God and the world. And although Aquinas reinterpreted the philosophical tradition in the light of the doctrine of creation, creation itself remained a matter of revelation.
In discussions of St. Thomas’s “philosophy,” the first question of the Summa—“The Nature and Extent of Christian Doctrine”—is often overlooked or ignored. Either it is assumed that Aquinas was a “metaphysician” interested in doing things like proving the existence of God, or it is assumed (by the more Thomistically sophisticated) that Aquinas owned two hats—one clearly labeled “theologian” and one clearly labeled “philosopher,” and that he was constantly switching hats. The trick for the astute observer is to know which hat St. Thomas was wearing when.
It is true that Aquinas made a distinction between the articles of faith and the preambles to the articles of faith (1.2.2) among which he included the existence of God. However, in 1.1.1, Thomas made it clear that another knowledge is needed besides that which philosophy provides because philosophy is not capable of bringing a person into that union with God which is his or her final end—a knowledge which is accessible only through revelation. The need for a sacred science (sacra doctrina) of revelation is provided by theology, which is distinguished from that “natural theology” that is part of philosophy (1.1.1). Aquinas thus made it clear that the task that he had set for himself in the Summa was not that of a philosopher, but that of a theologian—whose task it is to “treat of whatever belongs to the Christian religion . . . to set forth whatever is included in sacred doctrine . . .” (Prologue). Though he sometimes discussed philosophical questions and used philosophical tools to articulate theological ideas, the hat that Aquinas wore throughout the Summa Theologiae was labeled “theologian.”
That Aquinas was operating as a theologian is evident in that (as I have tried to show) the Christian doctrine of creation provides the key to unlock his “Treatise on God.” The doctrine of creatio ex nihilo provides the foundation for the distinction between the world and God marked out by Sokolowski and others. Aquinas used this distinction to advantage in reworking another distinction (that between essence and existence) which he had found in Ibn Sina. In giving priority to existence over essence, in speaking of God as self-subsisting “to be,” Thomas was able to describe God as the “Wholly Other” who alone exists necessarily and who has freely given existence to creatures. Since God and creatures are not component parts of the sum total of reality, Aquinas did not find it necessary to understand creation as a limitation of God’s power. God does not begrudge existence to creatures. Neither, however, is God identified with creatures in any manner. Creation is not a part of God. God is present to creatures (not in a panentheist manner), but through the creative act by which he gives them existence.
The radical distinction between Creator and creatures introduced by the Christian doctrine of creation could have led Aquinas to endorse a more radical “agnosticism” than that which he actually espoused: “It may be all right for ‘simple believers’ to talk about God, but theologians know that the name of the deity is ineffable.” But Thomas could not wholly embrace the via negativa of a Maimonides. While admitting the limitations of language about God, Thomas took seriously a religious tradition that spoke of God acting in history, of revealing himself in his covenant with Israel, of becoming human in Jesus Christ, and of showing himself to be Love, Wisdom, and Justice. Creation was (again) the key to Aquinas’s discussion of theological language. Although the Wholly Other God does not resemble creatures, creatures have some resemblance to God, and to that extent reveal something of his nature. Although (I have suggested) Aquinas expressed this using the philosophically Platonic language of exemplarism and participation, the context for this discussion is not a doctrine of emanation, but the theology of a God who as first cause contains super-eminently within himself the perfections that he has freely bestowed upon creatures in giving them existence.
Finally, the source for the model of intentionality that Aquinas used to illustrate the doctrine of creation was that history of revelation witnessed to in Scripture and tradition. The God of the Scriptures is not (like the God of the Nominalists) a God who has been revealed as sheer unrestrained power and will. Despite protestations to the contrary, Ockham, Biel, Luther and Calvin were resorting to a philosophical construction, not a biblical one. The God of Absolute Power is the result of a failure to mark correctly the Christian distinction between the world and God. The voluntarist God is ultimately an impoverished God because it must compete with creatures. Both the Pelagianism of Biel and the predestinarianism of the Reformers indicate that they construed God and creatures to be part of the same order. If God is simply the biggest thing around, then grace is either unnecessary to the spiritual elevation of the creature to the supernatural order (semi-Pelagianism—Ockham and Biel), or it must be imposed in a manner that overrides the creature’s will (determinism—Calvin and Luther). In either case, God must be absolutely free to do whatever is conceivable, for (since both God and creatures are essentially “wills”), only so can we guarantee the omnipotence and independence of God’s will over against the autonomy of the creature’s will.
The God of St. Thomas (and the God of Scripture), is not, however, this God of sheer omnipotent power. He does not need to be. The God revealed in the Christian tradition is a God who has created intelligibly, a God who acts purposively. This God loved the world into existence and made it good. He hates nothing he has made and has revealed his love and fidelity in his covenant with Israel. This is the Wholly Other who has come close to us in Jesus Christ. Such a God does not need to reject some in order to love others. This God is willing to share his life with us, and is not lessened in doing so. In emptying himself to become human, he did not cease to be God, but assumed humanity into himself. As Aquinas pointed out, God’s omnipotence is not demonstrated in the production of countless possible worlds, but in the redemption and re-creation of this world that has fallen into sin.