To modern ears, having forgotten the ontological and swimming in the ontic, this sounds strange (as, perhaps, does the Heideggerian terminology here). God is in His heaven and we are on earth; divinity is "up there", and we are "down here", and only a madman would question that this lower level of our "two-story universe" is populated with beings, and therefore, with being. It takes a quite radical readjustment of our entire way of thinking to understand what Plato could have meant to assert a unity between divinity and being.
The first thing that needs to go in our entire way of thinking is what a prominent Orthodox blogger, Fr. Stephen Freeman, has referred to as the "two-story universe" (along with its concomitant theological outlook which various prominent Catholic and Protestant bloggers have referred to as "moral therapeutic deism"). God and the universe are not two separate components or pieces to the totality of reality. Rather, God IS the totality and fullness of reality, or as Plato phrased it, the "All of being". And if the universe is populated with beings, it is because it shares in and participates in the radiance of that which is most properly Being - God.
The second thing that needs to go is the idea that divinity is a binary state. Catholic and Orthodox Christianity scandalizes the modern world by its radical assertion of man's deification or theosis - that, in the words of St. Athanasios the Great, the Pope of Alexandria and champion of orthodoxy against Arius, "God became man so that man might become God."
The Byzantine theological tradition understands theosis in terms of participation. Despite its protests to the contrary, Orthodoxy's conceptual framework was influenced heavily by Neoplatonism, although its spiritual foundation lies entirely and completely in the monastic experience of prayer and sanctification. The Cappadocian Fathers developed the concept of God's "energies" or participatory action in the world, a theology which would become formalized by St. Gregory Palamas, the Archbishop of Thessaloniki in the late 14th century. Palamas distinguished between the ineffable "Essence" of God - God as He is in Himself, by nature, apart from any participation - and the "Uncreated Energies" of God. The contemporary Greek philosopher Christos Yannaras defined "energies" (rather controversially, among those who posit a stronger separation and reject absolute divine simplicity) as "the capacity of a hypostasis to be known and participated in", and as no creature except Jesus Christ is God by nature, it can be easily seen that the Essence/Energies distinction serves to present the mystery of man becoming God by grace.
Theosis is also a process, borne out of repentance and prayer. As any process, it is attained in degrees, passed through stages, and blossomed in a growth characteristic of any form of life, of which spiritual life is really the analogue to which all other life should be compared.
And so divinity, as participated in, is a matter of degree.
Divinity can be found in its fullness, even when participated in. This can be illustrated by reference to the famous filioque controversy. Orthodoxy has always insisted that the Father is the single principle from which the Son spirates - while admitting that the Son bears a role in that process, participating the procession of the Spirit from the Father. As the Logos is the perfect Image of the Father, He perfectly shares in whatever the Father does, and that includes the procession of the Spirit - including, as the Latin tradition insists, being the causa of the Spirit, the cause of His divinity. From a Byzantine Catholic and eirenic Roman Catholic or Orthodox perspective there is no contradiction between the filioque and the Orthodox theology, because divinity - as being something that can be participated in - is an energy. We balk at calling the Son the aitios or arche of the procession, but nonetheless He does join, so closely that it is "from a single principle", to whom must properly be attributed the name of the Father, with the Father in everything the Father does. That includes being the source or cause or Latin causa of the Spirit, which would include being the source of His divinity. Other Orthodox formulations of the Son's role include the "energetic manifestation" of the Spirit "resting on" the Son, and the procession of the Spirit "through the Son"; in my opinion the clearest explanation is a distinction between the "energetic procession" of the Spirit from the Son and the "hypostatic origination" of the Spirit from the Father.
Divinity can also be found in partiality, in the imperfect saints. These saints are said to be "divine" insofar as grace - created and Uncreated - is growing in them, but also "divine" insofar as they are images and likenesses of God, reflections of the Father, little icons of Christ. As we refer to a picture by the name of the subject being drawn, so we call the saints by the name of the God whose image they are being formed into. God is the standard or prime analogue to which we are icons, and insofar as we resemble Him, He is present in our soul (by "essence, presence, and power", if we are Thomistic by inclination). We participate in the Uncreated Grace, the Uncreated Light of Tabor, insofar as our souls are "created grace", created and molded anew by God. We participate in the Uncreated Grace precisely by becoming created grace - not that one is the cause of the other, but simply that they are two ways of saying the same thing. Gratia creata and gratia increata, debated so bitterly between East and West, are ultimately nondual.
Plato adds his insight by showing us that insofar as we are “like God” – “divine” in a sense – we are like Absolute Being, Who is God. Theosis is a process of becoming real.
O God, lead us from the unreal to the Real, from darkness to light, from death to immortality. Shanti, shanti, shanti.
There are of course those who have heavily criticized me in past conversations for referring to Our Lord Jesus Christ as a creature, or as a "human person", including some quite well-educated and well-respected Catholic and Orthodox bloggers and amateur theologians (including Nathaniel McCallum, among others). In my defense, I profess the orthodox Chalcedonian faith of Jesus Christ, True God and true Man, possessing human and divine natures in one hypostasis (although I admit the orthodoxy of the Cyrillian formula "one Incarnate Nature of God the Word", which I hold to be convertible with the Chalcedonian formula).
However, my understanding - which I take to be properly characterized as nominalistic in a sense, and which McCallum thought was closer to Platonism - is that any adjectival characterization of a hypostasis, or of any substance or "thing" or subject, is a "nature", broadly speaking (without making any distinction between "nature" and "accident", as accidental determinations of Christ's being are not under discussion). In other words, to speak of a hypostasis as having a human nature is, BY DEFINITION, to speak of it as a human hypostasis. To say that Christ possesses a human nature is, BY DEFINITION, to speak of Him as a "human person" - and likewise, to speak of Him as possessing a divine nature is to speak of Him as a divine person. To say that Christ was human is to say that Christ was a human person; this is simply how our everyday language works.
This is not Nestorianism (a bizarre allegation), because He is one person, who is both divine and human. Unlike McCallum, I do not admit of any "personal properties" or adjectival characteristics proper to a hypostasis distinguishable from natures; I do not admit that one can speak of a "human hypostasis" without having already mentioned the nature (as if "humanity" were the hypostasis, rather than the nature). To do so would seem to divorce a hypostasis and the hypostasis' being from their nature, and it reifies "nature" in the process (making "nature" something that one could possess, like a thing, rather than making it a statement about what the hypostasis is). To say anything *about* a hypostasis is to give its nature (or accident).
I have also come under criticism for calling Jesus Christ a creature. Yet any proper anthropology must do so, for the human body and soul are Christ *are* a creature (and, contra popular Cartesian dualism, one must say "a creature", not two creatures). Bodies and souls are not something that humans possess, and if Christ truly became Man, He became a man.
(Theologians will correctly say that Christ's human nature was human nature itself, not just one instantiation of it, and hence human nature itself is redeemed and only awaits our participation - we are not only become real, but becoming human, through theosis - but the fact remains that Jesus of Nazareth was a man, who had a body, living in a certain time and place, with a height, weight, blood type, etc. - a particular, not a universal.)
I am my body. I am my soul. Christ *was* His body. Christ *was* His soul. His body was a creature. Therefore, by a simple valid syllogism (BARBARA), Christ was a creature. That is the full thrust and paradox of the Incarnation - "the Creator became a creature, so that the creature might become Uncreated". A very wonderful book on Orthodox theology by Fr. Daniel Rogich is entitled "Becoming Uncreated: The Journey to Human Authenticity", and the flip side to this paradox is that Christ became a human creature. He remains the Creator in the process. Nowhere in the entire corpus of Patristic literature is this denied, or the statement "Christ is a human person" rejected. Rather, what is constantly and incessantly affirmed is what has been affirmed here - Jesus Christ is God made man, with the human and divine natures subsisting in one person, the God-Man, 100% God and 100% Man.
Finally, there are those who will object to my Hindu prayer at the end of the essay. The prayer is entirely and utterly orthodox to any Christian. If one objects to the word "shanti", he may take it up with the quite Christian poet T. S. Eliot, who employed it quite as freely as I do without looming under any cloud of heterodoxy.