This article continues from part II.
Skipping ahead, from the 11th through the 13th century, a new phase of Christian humanism arose – in the thought and work of “scholasticism” – a movement in Christian thought that is understood by historians to have its intellectual foundations in Augustine, its early formulation in the work of Anselm of Canterbury in the 11th century, and its pinnacle in the grand system of Thomas Aquinas in the 13th.
The medieval scholastics continued and intensified the high humanist evaluation of human reason. As historian of science Edward Grant has comprehensively shown, no line can be drawn between the Middle Ages as a supposed “age of faith” and the 17th and 18th century “age of reason,” for both ages shared “the profound conviction that their beliefs could be reasonably demonstrated” and “medieval university scholars and teachers . . . placed a heavy reliance on reason,” and in fact, “in the history of civilization, they were the first to do so self-consciously on a grand scale.” Building on over a millennium of Christian thought about the Genesis portrayal of the imago dei, passed on from patristic thinkers such as Justin Martyr and Augustine of Hippo, the scholastics argued like this:
“If we are images of God, and if God is eternal, it follows that we cannot be images of God in our physical and corruptible flesh since flesh is not eternal. But if our flesh is not eternal, what is? The answer is obvious: our soul.
“The soul, however, was believed to have more than one part. The lower part served to animate the body and enabled it to move around. That is something we share with the animals. But the higher part enabled us to think rationally and comprehend abstractions, and that is something we share only with the angels and God.
“The [scholastics] therefore maintained that human beings are images of God in the higher, rational part of the soul, and that reason is the greatest natural gift we have.”
This theological understanding of human reason as God’s highest gift and very image in us gave a tremendous theological push to medieval Christians’ desire to understand God, themselves, and their world in rational terms. For they concluded such an amazing gift must be given for a purpose, “not to be squandered or neglected, but used appropriately in the service of the Giver.” For medieval Christian thinkers, reason was far from the opposite of faith. Rather, it was a treasured instrument given to us to use in service of our creator. It was something like being given a Stradivarius violin: we must use this instrument with very great passion, care, and discipline in all of our pursuits, including the pursuit of scientific knowledge.
In fact, that pursuit was a subset of whole swathes of human work, for medieval Christians understood that God intended they apply the gift of reason to understanding and ordering the gift of Creation—for our flourishing—a belief grounded, again, in the cultural mandate of Genesis: for example, in the task assigned to Adam and Eve of naming the animals, or God’s charge to them to cultivate and keep the garden.
Theology of the world
So, to see how science and other sectors of work benefited from the theological convictions of Christian humanism, we need to turn now from the humanist theology of humanity to the humanist theology of the world.
Throughout history, humans have been tempted to two errors about the material world. On the one hand we have the error of the early Platonists, the Gnostics, and all other dualists. This is the error of observing the fallenness and difficulties of life in the material world, and deciding that material stuff, itself, is evil; in fact, it is anti-God. For those caught in this way of seeing the world, the only way to attain human flourishing is to seek to transcend the material in search of the purely spiritual. Sadly, as I’ve suggested, super-spiritualizing tendencies in modern American evangelicalism have brought the church close to an attenuated version of this approach, which sees the material world as, if not evil, then at least spiritually irrelevant – thus deepening the faith-work problematic.
On the other hand we have the error of the ancient Epicureans and the modern materialists—both those philosophical materialists who deny the existence of a spiritual reality and see physical and biological causes as “all there is,” and those “lifestyle materialists” who buy the Ecclesiastes embrace of the physical world as our only end: “eat, drink, and be merry, for tomorrow we die.” Now, it’s easy to see that the Gnostic, ancient or modern, devalues the material world. But in fact ironically the materialist devalues it too, even while making it ultimate. How? By separating the pursuit of material goods from their origin and meaning in God. Again, and at the same time as it has courted the gnostic error, American evangelicalism has also ironically fallen into the materialist error as well: operating at work in ways that mirror the materialism of the surrounding culture – and thus treating God-ordained material means to flourishing as ends in themselves that allow for no connection to faith or spirituality; or, bluntly put, as idols.
Obviously, neither of these incomplete approaches to the material world provides the impetus needed for human pursuit of scientific and technological knowledge—and so science did not develop either among Gnostics or among materialists. Rather, it emerged in a culture that took a third approach to the material world—an approach that turns out to be one of the most central theological ideas of the Middle Ages, and a linchpin of Christian humanism: sacramentalism.
By definition, sacramentalism is the idea that physical matters and actions can be vehicles of spiritual or divine activity and presence. In short, material things can be God’s love, grace, and glory made visible. Let’s take one very influential representative thinker. Gregory the Great, the great “monk pope” and spiritual father of the Middle Ages, whose writings filled the cupboards of the great monastic libraries, insisted that while pastors or laypeople are engaged in the active life, everything in their experience and in the world becomes a potential instrument of God’s direct, special communication to them. Chance meetings. Storms. Landscapes. Crafted objects. A thousand other things. God is always speaking to us, if we but have ears to hear and eyes to see. Gregory emphasized “God’s involvement with creation and the sacramental presence of spiritual truths in the things of this world.”
Historians Robert Markus, Bernard McGinn, Jean Leclercq, and others take Gregory to have been a hinge figure – a turning-point influence in the history of Christian spirituality and practice. It is safe to say that Gregory contributed to the sense of God at work in the world and in our own embodied, material, social, and cultural experience that became part of orthodox Christian belief and practice for the whole period from his time right up to the Reformation—and, in many circles, even after this period. This was not pantheism, but rather the sense of both God’s glory reflected in creation and God’s grace working through ordinary things in creation.
In a moment we’ll get to the question of why Christians would believe this. But for now, we can see that such a belief would lead to a very different relationship to the world we live in. If transcendent spiritual reality manifests itself in and through created material reality, then all creation is in some sense a reflection of the Creator. Well – we can begin to see how such an understanding might motivate scientific investigation and other pro-flourishing work!
But first, why should Christians affirm sacramentalism? The most central answer is quite simple, and it goes to the heart of the Christian Gospel. We may believe materiality can communicate divinity not only because the creation bears the imprint of the creator – though that’s true enough. No, there’s a much closer relationship between God and his creation than that. For the Christian faith teaches that God in fact came and dwelt in his creation, making himself part of it as he incarnated himself in the physical, historical man Jesus.
Medieval Christians, far from seeing the Incarnation as a kind of one-time, bizarre aberration, understood it as the paradigm, the model, for everything that follows. The Incarnation was the linchpin of medieval theology. The Gospels were by far their favorite part of the Bible. The moment at which the angel announces this stunning miracle to Mary – the so-called “Annunciation” – was their most-painted devotional subject. And sacramentalism was their most typical mode of seeing the world.
Of no other world event can it be more correctly said, “This changes everything.” In the Incarnation, God’s mysterious presence in and through the created world was solidified and made vividly real. And sacramentalism grew out of Christian reflection on that event. In the East from the 9th century on, sacramentalism underwrote the theology and practice of writing and venerating icons, and since then, it has by extension underwritten all Christian art. Ever since the coming of Immanuel, God-with-us, God has remained for us not only transcendent but also immanent. Ever since, “no part of life remains untouched by his presence.”
Sacramentalism also provided the seedbed for the pursuit of scientific knowledge, especially in the high-medieval scholastic period of the birth of the universities (from the 11th to the 14th centuries). In part, it did this by birthing a truly devotional, awe-filled approach to that pursuit. Think about it: when we may look at the natural world not only as the arena of God’s work but as a physical reality that reflects his divine glory, then how else would we approach it but with awe and wonder? And since medieval and early modern followers of Christ indeed believed this, they approached their study of the created world not only out of a duty to apply the gift of reason, but also out of a sense of awe that the world is a conduit to God’s presence and glory. Should it surprise us, then, that the natural philosophers of that age spent hours and days and years of their lives in meticulous proto-scientific experimentation and hypothesizing?
And sacramentalism also meshed with the humanist anthropology we have already examined: a way of seeing human beings that highly values our rational capacities, and that readily applies those capacities, with awe and wonder, to “thinking God’s thoughts after him” in the pursuit of scientific knowledge – and indeed of all sorts of knowledge.
Again, this confluence of sacramentalist and rationalist approaches to the world reached a new peak during the scholastic period of the birth of the university, with its intensified emphasis on the rational agency of human beings. The characteristic scholastic humanist emphasis was on our ability to access, through exercising our God-given faculty of reason, “a body of knowledge sufficient for achieving order in this world and blessedness in the world to come,” as historian R W Southern put it. But this confidence drew not only on a high anthropology, but also on a trust – which we can see vividly illustrated for example in the story of medieval Christian scientific pursuits – that the universe is intelligible, reflecting (sacramentally) the supreme rationality of the Creator.
This confident search for knowledge of the world was eventually pursued through empirical method, driven by a belief that, although the created world is sacramentally linked to God, its phenomena operate in some sense by their own innate, discoverable rules.
While the late-medieval rise of a more empirical scientific method eventually trumped scholasticism’s “text-oriented exegetical method,” and “the rising new science scorned scholasticism for its lack of empirical grounding,” there is no question that the scholastics’ continuation of early Christian humanism, including its emphasis on the intelligibility of the God-created universe, the special role of human beings made in God’s image in discovering and unpacking the principles of that universe, and the great confidence in the part of that image that is human reason, set the stage for the rise of the sciences and other whole work sectors in the West.
This article continues (and concludes) in part IV.
 David N. Bell, Many Mansions: An Introduction to the Development and Diversity of Medieval Theology (Kalamazoo, MI: Cistercian Publications, 2000), 83.
 Bernard McGinn (Growth of Mysticism: Gregory the Great through the 12th Century [New York: Crossroad, 1996]), tells us that the writings of Gregory the Great were more prominent than those of any other postbiblical author.
 Carole Straw, Gregory the Great: Perfection in Imperfection (Berkeley: University of California Press, 1991), 50.
 Armstrong, Medieval Wisdom, 22.
 R W Southern, Scholastic Humanism and the Unification of Europe, vol. 1: Foundations (Cambridge, MA: Blackwell, 1995), 5-6; cited in Zimmermann, Incarnational Humanism, 90.