EP.01 Christological Introductions: Terms and Definitions

Added: 2026-05-16

[00:00:00]As this is going to be the first video of many that will go over the Christological understanding of the Oriental Orthodox Church, it makes sense to introduce the series with the most foundational and easily confused section, the terms and definitions. We will go over what different words and concepts mean and how they can be applied to Christology.

[00:00:17]The first term we should go over is physis, sometimes pronounced as phusis.

[00:00:21]Physis is the Greek word for nature.

[00:00:24]Now, a nature is a reality that can receive predicates. In other words, attributes can be given to that reality and the reality itself is the subject that has those attributes. For example, Kairos is the reality and tall is the predicate or quality given to him.

[00:00:37]Hence, tall exists in Kairos. Saint Severus of Antioch says in his letter six about nature, "Enough has, I think, been said about essence and hypostasis, but the name nature is sometimes taken in place of essence, sometimes in place of hypostasis. For even the whole of mankind we call comprehensively nature, as it is indeed written, for all natures of beasts and of birds and of reptiles and of things that are in the water are subjected and are made subject to human nature. And again, we speak of one nature in reference to a single man, Paul, for example, or Peter or maybe James."

[00:01:11]As Saint Severus said, there are two definitions of physis or nature, particular and common. The particular refers to an individual thing, like a human or a rock. Attributes such as tall, short, skinny, and fat are predicated to the human and attributes such as gray, white, big, small are predicated to the rock. Hence, the human and the rock are the individual realities and the qualities are predicated upon each. There's also nature as the common reality. This is a reality that is shared by many things.

[00:01:40]For example, the common human essence or the universal human nature is a reality that exists abstractly and qualities such as animality and rationality are given to it. Again, the reality is that which is predicated upon and the qualities are those that exist in what it is predicated upon. In simple terms, the common nature is just what is shared by all humans, which are all the qualities of being a human.

[00:02:02]Because physis can be used in multiple ways, the fathers used different Greek and Latin words to refer to the particular or to the common. In Greek, these terms are hypostasis and ousia.

[00:02:12]Hypostasis is the equivalent of an individual reality. For example, an individual human is a human hypostasis, and an individual rock is a rock hypostasis. The two words making up hypostasis are hypo, which means under, and stasis, which means standing. Put together, it is read as the word understanding, which is philosophically rendered as underlying reality or simply just reality.

[00:02:35]So, in the examples of humans, I, Kairos, have my own hypostasis, and you, the viewer, have your own hypostasis.

[00:02:41]Since we are of different hypostasis, this is what makes us different humans, but both of us still have the common human nature.

[00:02:48]This common nature in Greek is ousia.

[00:02:51]Common nature is that which indicates what all the hypostasis or individual realities under a specific species share.

[00:02:57]For example, you and I share the common human essence of being human, or the two dogs, Gracie and Atlas, share the same dog essence. This common essence is why you and I both share certain qualities, such as animality or rationality, but we are different because we each have our own hypostasis. See how Saint Basil defines ousia and hypostasis in his letter 214.

[00:03:17]If you ask me to state my own view shortly, I shall state that ousia has the same relation to hypostasis as the common has to the particular.

[00:03:24]Every one of us both shares an existence by the common term of essence, and by his own properties is such and one and such and one. In the same manner, in the matter in question, the term ousia is common, like goodness or Godhead or any similar attribute, while hypostasis is contemplated in the special property of fatherhood, sonship, or the power to sanctify.

[00:03:45]Now, the Latin version of these words is also something we should go over.

[00:03:48]First is natura, which means nature, and is the Latin equivalent of the Greek word physis. So, it's the same idea.

[00:03:55]Natura can function for any particular nature or the common nature, just like physis.

[00:03:59]Next is substantia. This is the Latin equivalent to hypostasis. The word sub means under, and stantia means standing.

[00:04:07]Again, it has the same function of underlying reality or simply just reality.

[00:04:11]Next is essentia. This is the Latin equivalent of the Greek word ousia. The function of ousia, which we said before, picks out the common essence, like being a human or being a dog.

[00:04:21]So, to sum it up, nature can be understood in two ways. In the common sense, it refers to what is shared by many individuals. In the individual sense, it refers to that same nature existing as a particular individual, distinguished from others by its own properties.

[00:04:35]Now, we can turn to the word person, or prosopon in Greek.

[00:04:39]Before Chalcedon changed the definition, prosopon commonly referred to an outward face, appearance, or mask.

[00:04:45]To understand this, think of a play with multiple actors. Each actor is a distinct human being, but each one puts on a costume and mask in order to play specific role. That outward role or appearance is what prosopon originally pointed to.

[00:04:59]This means that prior to Chalcedon, a person didn't have any real metaphysical or real significance, like nature does.

[00:05:05]See what St. Cyril says. In confessing, therefore, that the Son is consubstantial with God the Father, but exists in his own hypostasis, we say that they are united in a way that both conjoins and separates them. We join perfectly by the binding bonds of identity and distinction of personages, that is to say, of names, and the otherness of hypostasis.

[00:05:25]For St. Cyril, person is simply a name, and this would mean person is like a mask or an outward expression.

[00:05:31]Now, with a person, there are two definitions. First, an enhypostatic person. This is simply meaning a hypostasis with a person. This is exactly what a normal human is. You have your real existence, but then your outward appearance or mask that exists in your human being, and is the true identity of that being.

[00:05:49]Second, there's an anhypostatic person, which means a person with no substance of its own, merely a name. This would literally just be a mask with no real reality.

[00:05:57]For example, an enhypostatic person would be my real name indicating my particular being and an anhypostatic person would be a name indicating something other than a substance. That will be all for this video. Next part, we will go ahead and explain Miaphysite Christology and how the terms we just learned relate.