Living for the I AM: The Implications of God as Subsistent Being

[A term paper I wrote for my course Philosophy for Theology at Davenant Hall. This version does not include citations: for those get the PDF here.]


Not everyone likes philosophy,1 and often this stems from the widespread impression that it is of no practical use. Philosophy, many believe, is simply recreational speculation. Generally speaking, philosophers themselves disagree, and this paper will agree with the philosophers.

To be more specific, philosophy can actually be of considerable value for the average Christian, if not for his own direct reflection then at least as deployed carefully by his teachers in the faith. In fact, even some of the most obscure and abstract metaphysical claims can have immense practical utility. This paper will highlight one particular example. The metaphysical doctrine of God as ipsum esse subsistens, subsistent being, in which the perfections of all real beings participate according to their diverse limited essences, funds a powerful hermeneutic for creational and biblical symbolism and key insight for practical piety. God's perfection as pure act, in which all creaturely acts participate in limited ways, highlights God as the one in from whom, in whom, and to whom all thing exist that each without exception declares His glory.

What this claim means all by itself might not be self-evident, so it shall require some unpacking. The first order of business is to define what it means to call God ipsum esse subsistens and the implications for the doctrines of divine perfection and the creation of all other beings. As perhaps the most fundamental doctrine of the Thomist stream of the classical theism, it plays a critical role in everything further. If this doctrine is itself practically valuable for the Christian, then the rest of the enterprise surely has promise.

Ipsum Esse Subsistens

That God is rightly called, or perhaps (in a certain sense) defined, as ipsum esse subsistens is a key point of the Thomist philosophical tradition. God is being itself subsisting, "existing" as such in pure, unlimited perfection. This idea, though rather abstract at first, is rich and full of significance, so it will be necessary to elaborate on it in some detail. First to order is simply definition.


To say that God is subsistent being requires a brief sketch of the terms. "Being" here is not a noun but a participle, and it can be substituted with the infinitive "to be" (matching esse in Latin). This refers to the very activity of existing. Being in this sense means an act (not, of course, necessarily a conscious one), the act of self-presentation to the world of real beings. All things which really are are acting simply in standing out in the real world. Clarke explains thusly in defining being with respect to the word "is":

What does "is" mean? It is so fundamental that it is impossible to define it by anything clearer, or by setting it off as a class within a wider class, as is done in ordinary definitions, for outside of it there is nothing. We all already know implicitly what it means, because we know how to use it meaningfully, though it is not always easy to spell it out explicitly further. Metaphysics tries to do this. One way is to call up paraphrases, for example: "exists," or---perhaps more evocative---"presents itself": a being is that which is actually present in some way, presents itself as standing out from the darkness of non-being into the light of being.

For all creatures, their being in this sense---their activity of existing---is really distinct from their essence. For a dog to be involves a composition of two principles: the "dog"-ness and the being. The nature of a dog is the same whether any particular dog exists or not, and existence as such is not inherently disposed toward a mode as a dog. When existence is snapped into a specific nature, however, the result is a real creature. Nature, or essence, in this sense limits existence to a particular way or mode. In itself there are no limits to being as such, so that to exist might in principle mean all perfection and the full range of possible activities. However, when a particular creature exists, much (even most) of this potency is entirely cut off as quiddity of the exist-ent restricts this fullness of being to a specific set of potencies.

God, however, transcends this distinction. He is perfectly simple, so that for Him to be is to be God in an equation of exact identity. There is no difference or distinction of any kind between God's "nature" and His act of existing. God simply is He who exists, the full and unlimited I AM THAT I AM.

A Brief Case

A definition of God built on so many levels of intricate abstraction often raises eyebrows, naturally. It is far beyond the scope of this paper to defend this kind of philosophical approach in broad principle, but a few steps of specific justification for the doctrine in question may in fact be useful to establish its credibility given some general premises about the role of metaphysical thought in theology.

One of the most straightforward arguments that God simply is subsistent being comes from Aquinas in Summa Contra Gentiles. He argues as follows:


By definition, existence refers to being in actuality, as opposed to potentiality.2

If an actuality belongs to something that is other than itself, than it stands in as potentiality to that actuality.

If God's act of existence belongs to His essence as other than His existence, then God's essence is in potential with respect to His existence as actuality.

This cannot be, for there is no potential in God.

Therefore in God His nature is altogether identical to His existing: His nature is being.

Of course, this argument also depends on the accepting that there is no potentiality in God, but properly defined this claim should be self-evident given other general convictions about God. For example, if there were any potentiality in God, there would need to be another being in act to help actualize this potential, clearly compromising God's aseity and either making Him not the Creator of at least one thing or, perhaps, dependent upon His own creation, both of which need to be rejected.

Divine Perfection

A key area of theology in which this applies in a way especially pertinent to the concerns here is the doctrine of divine perfection. Divine perfection is one particular angle on God as subsistent being and pure act. Per Aquinas:

God is the first principle in the genus of efficient causes; and the first efficient principle has to be absolutely perfect. For just as matter as such is in potentiality, so an agent as such has actuality. Hence, the first acting principle must have maximal actuality and, as a result, must be maximally perfect.

He goes on to add that esse is the most perfect thing since it is the actuality of anything whatsoever. God as subsistent being thus means God is most perfect of all beings. He is maximally in act, simply existing in unlimited plenitude with all of the perfection that is possible for existence in any sense.

This brings Aquinas to a second point, however. All creatures participate in being from God. He is the unlimited act of existence, and creatures exist in a limited mode. What is unlimited, however, entirely includes whatever can be limited within the same category (e.g. an infinite set of numbers includes every possible finite set of numbers). So God's own being contains within itself, in a pure, unified, and undiluted form, the perfections of every creature, the fullness of actuality corresponding to every creaturely potency.

[S]ince God is subsistent esse itself, he cannot lack any of the perfection of esse. But the perfections of all things are pertinent to the perfection of esse, since they are perfect to the extent that they have esse in some mode or other. So it follows that there is no entity whose perfection God lacks.

There are two ways in which the perfections attributable to creatures can be said to exist in God. Some are "simple perfections," that is, they are perfect in and of themselves as such without any mixture of imperfection. An example of this would be goodness, which, after purging the concept from any unnecessary creaturely accretions, can apply literally to God. God is good. In contrast to this are what might be called "relative perfections." These are attributes which perfect creaturely potencies but are nonetheless defined with some mixture of imperfection. An example of this would be good eyesight. To attribute to someone excellent vision is to attribute to them a real but constitutionally limited kind of perfection, since vision as a sense belongs to materiality, which is a fundamentally imperfect mode of existence.3

God in Every Creature

That all perfections at all, including any kind attributable to any creature whatsoever, exist in God immediately lends itself to the next stage of the argument. If every perfection of every creature exists if the infinite being which God simply is, then the converse is also true: some perfection of God exists in every creature. This is a very potent4 conclusion with ramifications throughout the whole sphere of life for anyone intending to know God. To elaborate on this fully will require revisiting the composition of creatures from existence and essence.

Existence and Essence

Every real being is composed of existence (esse) and essence (essentia). A different principle is responsible for the reality that a being exists than is responsible for the reality of what being exists. In the Thomist tradition, the principle of existence itself is has no intrinsic limits. The real power of actual being qua being extends to all possible perfections, since to be always positively adds something to reality. Thus being is a principle of positivity, and positivity apart from a limiting principle of some sort can expand ad infinitum.

Essence, by contrast, is a limiting principle. What a thing is defines it in distinction from all other things, cutting off all other possible modes of perfection except those belonging to the nature which it actually expresses. Whatever perfections come with being a kangaroo,5 to be a kangaroo is quite determinately not to have all the same properties and powers as a star, a fish, a Segway, or a blackberry bush. Clarke explains:

[T]he principle of existence must be a maximum, an all-encompassing plenitude, with essences serving as limiting, diversifying principles within the fullness of existence itself, diversifying being by limiting it in different ways from within, partially negating the fullness of being by diverse, limited modes of existing... Essences are thus...intrinsic limiting or restrictive principles particularizing and finitizing each act of existence that is not the total plenitude of pure unrestricted existence, thus allowing for many different real beings, all limited participations, through different essences, in the unlimited fullness of existence itself.

Natures as Refractors of Existence

Essence, then, serves as something of a prismatic function relative to existence. Being itself is like a pure and full beam of the whitest and most intense light, and a specific essence is like an item of shaped and colored glass that refracts that light in a particular way. The beam "comes out" in a unique form and color, cutting off all of the other possibilities which belonged to the raw beam initially. This analogy is not perfect (primarily since essences are not real in the most literal sense prior to their union with existence in real beings) but is nonetheless very helpful.

The key for theological import, then, is unifying this idea with the definition of God in terms of ipsum esse subsistens. If God's nature is simply to be, that is, being itself, then He is like the white light, or perhaps the great Sun from which proceeds all of this brilliant white light. Every nature of every creature is thus like one of these little shards of glass through which His own infinite brilliance is refracted into a multitude of forms and colors. Every perfection of every creature begins eminently in God as the First Efficient Cause, and then proceeds in this manner to and through each of these beings so that each shines with some small portion of His brightness in some unique way. This radical vision of the world as the kaleidoscope of the glory of God is one of the most powerful of philosophical insights for Christian life, one which has two primary realms of practical ramification.

Being and Divine Revelation

In creation, God donated existence to a world of creatures, and among these creatures were men, made with reason. By reason, men are able to reflect upon themselves and other real beings, abstracting from matter through phantasms to perceive forms and acquire insight into essences, and in a sense into the very act of existing itself.

This ability to develop understanding about being by means of the intellect places man in a fairly unique place. Angels seem as though they must be able to simply perceive and understand realities in a simple act. Other creatures, such as animals, by contrast, have no ability to understand rationally at all. Men alone go through this process of sensing and abstracting, and thus men alone are potentially subject to education, in which by gradual exposure to many beings and events they come to acquire knowledge.

This reality of man as the student of being belongs together with the reality of every being as a limited participation in the total perfection of being, with this totality being understood as in some sense God's own nature. If God is ipsum esse subsistens, and every being of every nature acts out some limited mod of God's perfection, and man is able by his reason to acquire understanding by abstracting forms from sensation of these beings, then in the end man is able to acquire some limited knowledge of God's own perfection by his engagement with creatures. This chain is the where divine revelation begins, the process by which God makes Himself known, though veiled in creaturely forms, to mankind. The utility of grasping this chain of revelation in being is extensive, and the next two sections will unfold the significance of this in terms of general and special revelation.

General Revelation

"General revelation" refers to God's revealing of Himself in ways that are "general", that is, applicable to all men regardless of their status among the people of God. Per Romans 1:19-20:

For what can be known about God is plain to them, because God has shown it to them. Ever since the creation of the world his eternal power and divine nature, invisible though they are, have been understood and seen through the things he has made. So they are without excuse.

From the unique angle of identifying God as ipsum esse subsistens, general revelation is certainly the most relevant category. God reveals Himself by and in all that He has made, those beings with which unbelievers deal as much as believers. Every single creature reveals something about what God is, for they all exist in some particular way, channeling the infinity of being in some limited mode.

When speaking of general revelation, the doctrine of God as subsistent being drastically expands the scope of such revelation beyond what many would otherwise be inclined to assume. For even the unbeliever, every single real being in all of creation exemplifies some limited aspect of the divine perfection. This is why nearly all people are religious to some degree or another. However little a human knows, they have been exposed to other beings, and for every being to which they have been exposed, they have been able to grasp some part, however limited, of God's own perfection. In addition, though in fact few people are prepared to undergo this process, they can take some of what they have learned about God and integrate it with everything else they have known to attempt to get a better picture of exactly what kind of being God is.

Even when the observer is not fully aware of it, then, every single being in the universe constantly contributes to every human person's knowledge of God since its perfection is an expression in a limited mode of God's own perfection. For those who do not understand God as the united source of all such knowledge, it can be very easy to leave all of the different items of knowledge unrelated, missing the synoptic insight they can afford. Only the most diligent are likely to move beyond this to a unified conception of the ground of all being in God. Even so, it can provide a helpful framework for Christians articulating their claims to anyone. "Look at the ant" or "look at the trees" can be legitimate introductions to spiritual reflection since everything, even ants and trees, tells the knower something about being, and thus something about God.

For those who do recognize God, however, the recognition of Him as ipsum esse subsistens can have other uses as well. They can see in stars and trees and birds the perfections of God and consciously comprehend them as His own. Take, for example, a sunset. Someone who knows that God made all things and that they reveal who and what He is in their own limited way can see the sunset and integrate all that they understand about it into their concept of the beauty of God. By this greater understanding is achieved so that the man, in coming to know more about the sunset, is also coming to know more about the God for whom a sunset is simply a tiny sliver of His fully and unlimited being.

All of this comes into its highest in man, made in the image of God. As the image of God, there must be some special sense in which man of all creatures captures a uniquely comprehensive "slice" of divine perfection, so that knowledge of man provides a way to the richest form of knowledge of God available through creatures. Because God has formed the nature of man in this particular way, with so many layers and textures and facets expressing so many traces of His perfection, man is especially encouraged to use knowledge of himself to gain insight into God. This is both fitting and permissible even (in a sense and to an extent) before and apart from a particularly scrupulous process of "decreaturification" in our understanding, as Bavinck once said, "We have the right to anthropomorphize God because he himself theomorphized when he created human beings."

Nonetheless, using general revelation in this sense accurately is both laborious and complex, at least if it is to be understood rationally by the intellect rather than on a more basic, pre-rational level. Many have gone wrong, and even the most brilliant of men without the word of God have made some very egregious errors in their attempt to trace out the meaning of God's own being from their knowledge of being through creatures alone. This, then, leads to the question of special revelation, and especially whether and how it might relate to knowing God's being through the essences of creatures.

Special Revelation

The notion of God as ipsum esse subsistens seems at first glance to be most useful for understanding general revelation, since it highlights what the human mind can discern about God from its experience with creatures. Nonetheless, the doctrine is equally at home in and potentially useful for the use of special revelation in a number of ways. Just a few of these will be sketched out here.

Almost as soon as a reader opens a Bible, he finds the text speaking of God using very creaturely imagery. The Spirit of God broods over the waters like a bird, God speaks as though He had a mouth and vocal cords, He sees as though with eyes, He breaths into man's nostrils, etc. The Psalms describe God like a rock, a shield, a tower, a warrior, a stronghold, a shepherd, a light, a sun, and countless other created beings.

Most people, when they read that God is a rock, have enough basic understanding to recognize that, on the whole, God is more unlike a rock than He is like a rock. If asked about it, they will say that God is not really a rock, but that the rock is some kind of metaphor for something about Him. This is true so far as it goes, but it is not the whole truth. The clever reader may quickly get the impression that all such attributions are more or less arbitrary poetic license. It is very easy to simply say, "These are metaphors, and that is all there is to them." This is not strictly false in a sense, but it can certainly be quite misleading.

As seen above, God is subsistent being as such, and all real beings participate in His this in a limited mode according to their essence. This means that a rock is not a "thin" and arbitrary symbol for God, but rather that its very nature is to exist in some finite participation of God's own perfection. So its durability, shelter, and all other qualities point beyond their limited mode of expression to the the infinity in God which corresponds to them. Every perfection of a rock exists in God in a more perfect and eminent mode, therefore in a valuable sense God is precisely the Real and Transcendent Rock.

This is valuable itself even just inasmuch as it affords clarity and insight for readers of Scripture encountering the many names and attributes of various modes of applicability to God it uses. However, there is even more value than just this, and this value comes from taking special revelation as a guide and "cheatsheet" for evaluating general revelation. For men do not always readily perceive, at least consciously, all of the perfections of any given creature or the manner in which they point to their more eminent mode in God. Biblical metaphors and analogies can serve as a way of attuning the mind to these realities so that it is ever ready to a greater degree to perceive that which all things reveal about God.

Take as a very simple example the sun. Most people (particularly people of the modern day who spend most of their time indoors) will often taken the sun for granted and never really reflect upon it. However, Scripture connects the sun to God in several ways. It is associated with the highest authority in the heavens6, the face of the Lord7, and of course light in general.8 It is easy to get a general impression that the sun serves as a good symbol of the shining face of God. If a biblical reader were to discover this association in Scripture, realizing that these symbolic associations are based on how creatures actually participate in divine perfection allows him to go back into the world and observe the sun that he might discover more truth about God. By taking this objective character of the nature of the sun as replicating in a limited mode God's own being into consideration, he can reflect on more ways in which the sun reminds him of God. It stands "infinitely" high above the world, sustaining life through its light and heat. It is the light which brightens all things but is too intense to look at directly without damage. If the sun "hides its face" for too long, all creatures on earth begin to suffer. The parallels are rich and possibly inexhaustible, and this just highlights how man's knowledge of one of the most brilliant creatures he can perceive can enter into a potent union with his knowledge of God even through special revelation to illuminate both.

Exultation in Every Activity

If the chief end of man is to glorify God and enjoy Him forever, per the Westminster Shorter Catechism, then whatever is true about the way in which God reveals Himself to creatures must also have practical implications. To glorify and enjoy God requires knowing Him, and for this to be the chief end means that the knowledge of God must serve as a unifying orientation and reference point for all parts of life. So it remains to see how the identification of God as ipsum esse subsistens revealed in limited modes by creatures works itself out through human living.

God Revealed in All Creatures

Man is the image of God par excellence, but the doctrine of divine and creaturely perfection above means that in a lesser way and to a lesser degree every single creature is an image of God. If man (particularly in Christ) is the full body sculpture, then perhaps a squid is an oil painting of a fingernail.9 Everything, literally everything in heaven or on earth or under the earth, is a little icon of God's perfection. What this means for Christian living can hardly be overstated.

No man can know God10 except through creaturely means. God is invisible, entirely beyond the reach of the senses. The senses themselves are the necessary means for human knowing, and this means that what is made visible and tangible is necessary to the knowing of God by which pursuit of the chief end is possible. Physical beings are what tune the human mind into divine things. Joe Rigney puts it plainly: "Created things make eternal things perceivable...Made things make invisible attributes visible." 

This goes back to the previous section about general and special revelation. Real world creatures are the means by which people can know God, and thus necessary for them to glorify and enjoy Him. When a man enjoys his ice cream sundae, he is enjoying perfections which trace back to God's own being. If a man reflects on the pleasure he takes in a fictional world, he can realize that all of the qualities which make him enjoy it came through the intellect and imagination of the author, who in turn learned them from the real world, which ultimately derives them from God. Consistent attention to the good in all things opens up a world of spiritual understanding to enrich the vision of God.

The Perfection of God Without

The study of God's perfection in the perfection of creatures is not a purely academic enterprise. 11. The point is as practical as potatoes. Seeing the existing perfection of God in creatures opens, on the one hand, opens doors of contemplation and appreciation that bring forth praise and worship, and, on the other hand, also provides something of a road map for the kinds of activity that are worthy to undertake. To see that something is good in a limited mode is to see that it can become, or be integrated into a greater thing that will become, even more perfect. Perfection can be added to perfection, and the result become a world more thoroughly infused with the glory of God.

Scripture describes the eschatological goal of the world in terms of God's resplendent glory overflowing all things: "[T]he earth will be filled with the knowledge of the glory of the Lord, as the waters cover the sea."12 This is what all things are for and where all things are going. Seeing that all creatures, to the extent that they are perfected to the actualization of their full potential, perform this role of revealing glory, it follows that actuating greater perfection in unperfected creatures brings them closer to this grand end of the glory of God. As Richard Hooker said, "Everything, except for God, is not so perfect within itself that it cannot be improved by something outside itself." Man stands uniquely suited for this perfecting role, as he alone of all physical creatures can piece their natures by his intellect, and by this understanding act intentionally to realize all of their potencies.

The goal here is to maximize the display as the manifold perfection of God in the world by bringing all of the creatures in the world, which express His perfection, to their own maximum perfection. Possible examples abound. To train a dog is to realize more and more of the potential in its nature, bringing it closer to the display of the fullness of the divine perfection which its nature uniquely channels. To turn grain into bread, grapes into wine, mountainsides into monuments―all of this is to actualize latent perfections in the world God has made, so that His glory is even more fully revealed. This is in fact the basic material of the regular Christian vocation. Shoemakers, farmers, programmers, and entrepreneurs all do (or rather can do) the same. They take the beings around them, perceive in them what they are, what they can be, and what will bring them to be what they can be, and then they bring the divine idea into greater reality for that individuated being. Even in the most mundane of actions, like baking biscuits or pouring drinks, this pattern is at work. A little more glory, a little more light, peeks through to brighten the world of God's artistry. James Jordan puts it clearly:

Man is God's agent for the glorification of the world. The world was created glorious, but is to become more glorious progressively under the hand of man. "Glory" is a difficult concept to describe, but clearly it has to do with the revelation of God...[T]he work of man is to reveal God even more, and bring Him even more glory...This is the mystery of time, of growth, of history. It means something amazing, however: that even in the simplest of human actions, God's glory can be enhanced and His Person revealed more fully.

The Perfection of God Within

For a man to glorify the world around him, expanding the actual participation of the beings with which he is in community in the full perfection of their natures, is a great, vital, and awe-inspiring task, one which should occupy much of the Christian life. However, this outward work on the man on the world also correlates with an inward project. As Hooker noted above, nothing is so perfect that it cannot be brought to greater perfection by something outside of itself, and this applies to men just as well as to anything with which men work. Thus write after the former quote, Hooker wrote, "[T]here is nothing in the world, whether great or small, for which our knowing it or using it might not add a little to our perfection."

Thus the second great practical implication of this theology for Christian living is the project of virtue. Virtue is the excellence of the human person, the habits and characteristics which maximally actualize the potential with which human nature was designed. If God made man in His own image with a nature that provides the most intelligibly rich and comprehensive mode of finite being, then God is most revealed and glorified when men develop the virtues for which they were made to the greatest degree.

Each man is in a sense a little god, a tiny but especially broad synthesis of powers and properties that gives him the potential to reveal God's glory and elevate other beings to greater perfection in both a qualitatively and quantitatively superior way to most other creatures. In order to fulfill this grand task, however, he must develop his own perfections to the highest degree possible. Doing this both makes him a more glorious revelation of God himself and increases his ability to bring other beings to perfection.

This is a massive project, one which will have no end in this life. The perfections to develop are nearly infinite: natural virtues (justice, prudence, temperance, fortitude), supernatural virtues (faith, hope, love), knowledge, "virtues" in the broader sense of excellencies, which can apply to attributes as diverse as physical strength, artistic ability, emotional perception, rhetorical skill, and countless others.13 For a man to develop such qualities is to maximize his own actuality, to make himself a more perfect light by which to communicate the light of God's own being to the world around him.

What it takes to perfect the self, however, is for the self to be perfected as its potential is made actual by the activity of other real beings. This takes several forms, whether physical interactions in and of themselves (e.g. a drug bringing the body to greater health), learning from teachers, the enrichment of knowing as the intellect becomes other beings intentionally, or of course the supernatural assistance of the Holy Spirit. So a man who wants to glorify God and enjoy Him forever will seek to use every available means around him to perfect himself that he might be entirely fit both as a vessel of God's revelation to other beings and as a recipient of the divine vision himself.


Having concluded in with the observation that every Christian man is bound to make the best possible use of all things to fit himself to receive and represent the glory of God in creatures, it remains to briefly review the journey to this point. God, so the Thomists say, is in some sense defined as ipsum esse subsistens, that is, subsistent being itself. God is the full and unlimited plenitude of existence existing, maximally real and active in the most eminent way from every angle. Every real being has an essence that "channels" a limited mode of existence, so that its nature is to be in some real but finite participation in some aspect of God's own perfection.

From there is was clear that this basic framework has a number of implications for the Christian's understanding of revelation, both general and special, and the practical shape of the Christian life. It clarifies how God is revealed generally through the natures of all creatures, highlights the value and meaning of symbols and language in special revelation, delineates the use of all creatures for the Christian's knowledge of God, and provides a coherent logic for the Christian life focusing on perfecting every being as much as possible, whether another or the self. With such a rich vision of God, the world, and the human place in relation to both, the concept of God as ipsum esse subsistens is no mere academic proposition but a philosophy which is truly for theology.


Pardon the lack of a source for this bold claim.


For example, no one will grant that Kanye West is President of the United States just because he has the potential to be so.


Aquinas discusses all of this at length in ST Ia, q. 13.


No pun intended. Well, actually, it was.


Indeed, these seem to be quite considerable.


Genesis 1:16


Numbers 6:25, 25:4


It is curious Scripture uses this particular symbolism much less frequently that its obviousness would suggest. This could very well express the ancient need to guard against actual sun-worship, since that was such a common form of idolatry.


Forgive this ridiculous analogy, but it seems to make a valid point.


In this life, at least, though it is debatable whether it applies to the next


Not, of course, that in the end there is such a thing


Habakkuk 2:14


Nunchuk skills, bow-hunting skills, computer hacking skills...