How does the Incarnation work?

We saw in a previous article that the Incarnation is the means by which God shares his divine life with human beings, transforming them into his likeness, so that they can eternally enjoy perfect fellowship and union with him. As I will now argue, this has some interesting implications for (as it were) the specific 'mechanics' of the Incarnation.

How exactly does the eternal God 'become Man'? The most straightforward interpretation would have God literally transforming himself into a human being, exchanging his divine nature for a human one. But this is a non-starter. For losing his divine nature would surely entail losing the power to share the divine life with human beings. Hence on this simple account, the incarnation not only fails to fulfil its purpose, it makes said purpose impossible to fulfil.

The divine nature, then, must remain intact in order for the Incarnation to achieve its goals. That is why Christian theology has consistently taught that the Incarnation consists in the union of a divine nature and a human nature, not the transformation of a divine being into a human being.

But what exactly is this 'human nature' that the divine Word unites itself to? Well, one view is that it is simply a human body. The fourth century Christian bishop Apollinaris argued that in the Incarnation, God the Son simply took the place that an ordinary human soul would normally occupy. This sort of position is sometimes referred to as 'Word-flesh' (Logos-sarx) Christology. Its opponents charged that, here again, the view jeopardizes the efficacy of the Incarnation. Another bishop and contemporary of Apollinaris, Gregory of Nazianzus, put it like this:

The unassumed is the unhealed, however, that which is united to his Godhead is saved. If only half of Adam fell, then Christ assumes and saves only that half of his nature. But if his nature fell in its totality, then it must all be united to the nature of him who was begotten, and thus be saved in its totality. Let them not begrudge us our salvation in its totality, or clothe the savior with nothing more than bones and nerves and something which looks like humanity.

Let's try to unpack this a bit. If it is human nature as a whole that is to be regenerated and deified, and not simply its bodily component, God must unite himself to a complete humanity, both body and soul. Otherwise, God would not really be sharing his divine life with humanity at all. Further, and as we saw in the last article, the most important aspects of deification have to do with the character of the human soul, which is called to partake of God's love, perception, joy etc. Hence an Incarnation that failed to deify the soul would fall well short of what it promised.

For these reasons and others, the opposing 'Word-man' ( Logos-anthropos ) Christology eventually won out and became normative to mainstream Christianity, which affirmed that the divine Word of the Father and a particular human body-soul complex were perfectly unified in the person of Christ. The Third Council of Constantinople (680) went as far as to declare that there exist two distinct wills in Christ, one divine and one human.

This raises questions about the unity of the person of Christ, as it seems to imply two 'Christs', one divine and one human. I hope to discuss this in the next article.

"God became man so that man might become God"

Such was the "rallying cry" of Ancient Christianity, according to Prof. John Peter Kenney (2018, p.107). This statement pithily (and provocatively) summarises the Christian doctrine of the Incarnation. In particular, it connects nature of the Incarnation ('God became man') with its aim ('that we might become God'). It might seem natural to begin by explicating the former, before moving on to the latter. But sometimes the best way to understand what a thing is to look at what it does. We might therefore benefit from starting with what the Incarnation is supposed to accomplish, and work our way backwards from there.

The result of the Incarnation, then, is that it enables human beings to 'become God'. This obviously shouldn't be taken to mean that we are to become our own 'Gods'. The mere fact that we are and always will be creatures necessarily precludes this, since the divine essence includes absolute independence, and thus uncreatedness. In any case, Scripture offers some clarification on this point: "he has granted to us his precious and very great promises, so that through them you may become partakers of the divine nature" (2 Pet. 1:4). We are called to 'become God' in the sense of having a share in his Being, i.e. in his perfect Goodness.

This isn't quite sufficient. Indeed, we saw in another article that God creates by sharing his Being with his creatures, which may be said to reflect or participate in the Being of God, each in their own way. If that's right, then it seems that all creatures partake of the divine nature, just by virtue of being creatures.

But even so, the extent of the partaking varies from creature to creature. Not all creatures reflect God's being to the same extent. For example, since God is perfectly rational, creatures with rational capacities share in more of his Being than creatures that don't.

So, being called to 'become God' must mean being invited to share in far more of God's Being than that which we already partake in as rational creatures -- specifically, to participate in his divine life. To see as he sees, to love as he loves, to experience his perfect joy and peace, and to do so eternally.

The incarnation, then, is the means by which God offers the gift of Himself to humanity. This is true not only in the sense of sharing his divine life with us, but also in the sense of allowing us to enter into perfect fellowship with God, the Supreme Good, whereby we 'know Him fully, just as we are fully known', to paraphrase St Paul (1 Cor 13:12). This is why the ultimate outcome of the incarnation is spoken of as a marriage between redeemed humanity and the incarnate God (Rev 19:7-9). In fact, the two senses go hand in hand: we cannot possibly enjoy intimate union with God without being sufficiently like him, any more than mice can have deep friendships with human beings. Conversely, we cannot be changed into his likeness without allowing him to pour his life into us, which itself presupposes some degree of union.

Origen of Alexandria compares this process to a piece of iron acquiring the characteristics of fire when place in it:

"If, then, a mass of iron be kept constantly in the fire, receiving the heat through all its pores and veins, and the fire being continuous and the iron never removed from it, it become wholly converted into the latter (...) In the same way, that soul which, like an iron in the fire, has been perpetually placed (...) in God, is God in all that it does, feels, and understands"

This brings us to my final question: how exactly is it that God's incarnation in Christ brings about these things? Though I hope to write more about this in future articles, I still have some space for a few vague comments about this. The event of the Incarnation, as understood by historic Christianity, involved the conjoining of a divine nature -- the eternal Word of the Father -- to a particular human nature. This enabled said human nature to achieve what humans had thus far failed to do, i.e. to live a life of pure self-giving love and willing obedience to God, even to the point of death on a cross. This opened a way to reconciliation and union with God, so that all human beings could embrace the perfect intimacy that Christ enjoys with his Father. In Christ's own words,

"All that the Father has is mine; therefore I said that he will take what is mine and declare it to you." John 16:15

In other words, the Incarnation does not strictly end with Christ -- rather, it continues in the life of his people, who receive the divine life that he himself receives from his Father. Thus we have come full circle: God was made man, so that we might be made God.

Ex Nihilo & Ex Deo

Christian theology has always taught that God creates ex nihilo, from nothing. God's relationship to the universe isn't analogous to the one that holds between an engineer and his machine. The engineer merely arranges preexisting component parts in such a way as to make them serve a beneficial purpose. The parts themselves don't depend on his activity. The God of traditional theism, in contrast, gives every thing its being, not just its structure. Rearranging preexisting bits of matter doesn't strictly bring about new being, rather it changes the being that is already there. Hence, God's job description requires him to create ex nihilo.

This might seem odd, or even unintelligible at first : how can anything be brought into existence from nothing? When we create things, don't we always do so by putting bits of matter together?

But as strange as it is, creation ex nihilo is all around us, even though (and as we're about to see) our linguistic practises tend to obfuscate this. Take, for instance, the case of an object heating up due to being left out in the sun. The standard explanation of this, which we all learned at school, is that something is being transferred from the sun to the object. That 'something' is thermal energy, or simply heat. Our 8th grade science teachers would have us believe, then, that heat is a 'thing' that can passed on from one object to another, like a baton.

The problem with saying this is that heat, unlike a baton, isn't actually a thing! Rather, it is a way a thing is, just like colour, weight or shape. It doesn't have its own existence, it cannot logically exist without being had by anything (no such thing as heat without some hot thing). Therefore, unlike a baton, it isn't something that can literally be passed on from one object to another. When we say that heat is 'transferred' from the sun to the object lying outside, we mean to say that the object acquired a new way of being, namely being hot, as a result of the sun's acting on the object. Crucially, this new way of being isn't some preexisting part that was attached to or incorporated into the object -- parts can conceivably exist without the things that have them, ways of being cannot. Hence, the object's new way of being did not preexist the object. It was given to it from nothing.

The same lesson applies to all instances of so-called 'energy transfer'. In all such instances, an energy source brings about new ways of being in other objects, without literally giving them some preexisting thing. If this can be done by a burning ball of gas, surely it can also be done by God. The difference is merely one of degree: the sun gives the object some of its being ex nihilo, i.e. its heat. God, in contrast, gives things all of their being.

But there is more to the analogy. While the sun creates in the object its heat ex nihilo, this does not mean that the sun is radically unconstrained in what it can bring about. Specifically, it can give no more than what it already has. It is able to make the object turn hot, only because it itself is hot. We may say that the object acquires its particular way of being by 'reflecting' or 'imitating' the sun's particular way of being. There is therefore a sense in which the sun shares some of its own being with the object. Again, the same applies to other energy-sources.

If this is the way in which new ways of being are brought about within the natural order, there is no reason why God shouldn't bring about being in this manner as well. There is therefore a sense in which divine creation is ex deo, i.e. 'out of God'. God creates by sharing his being with the rest of reality, which reflects his being, each particular thing in its own way.

We may draw two conclusions from this: first, that divine creation itself is a self-giving act on the part of God, who 'radiates' his very self to creation. Secondly, all created beings, as Leibniz put it, express God to various extents, depending on how much of himself God shares with them.

"For with you is the fountain of life, in your light do we see light" Psalm 36:9