A Digest on the Trinity - Part 2: Essence, Persons

This article is the first of a series that will set out the doctrine of the Trinity in simpler and more accessible language, to lead people into greater and deeper contemplation of the one God who is also three. It will not begin from Scriptural foundations, but assume them throughout, as the aim is to provide a doctrinal digest. For excellent surveys of the Scriptural texts, see Robert Letham’s The Holy Trinity and Fred Sanders’ The Triune God.

Finding vocabulary

After the Ascension, the early church found herself plagued by heresies all around. To combat these heresies as unfaithful expositions of Scripture, the church struggled to find the vocabulary to articulate faithfully how God is both one (Deut 6:4) and three (Matt 28:19) at the same time. On one hand, we must say that there is only one God, but on the other, there were three distincts identified as the same God. It was Tertullian who first used the word trinitatis,[1]the word persona to refer to a concrete individual, rather than the common meaning of an actor’s mask,[2] and the classic formula that God is one in substance and three in persona.

The historical development at this point is fairly complex, with both Latin and Greek theologians using different words which each having its own connotations, and heresies continuing to abound. For present purposes, we will focus on the words the Greek theologians used: ousia and hypostasis, which roughly translate into “essence” and “person”. It should be noted that by the time of the First Council of Nicea (325), which was called to set forth orthodox Trinitarianism, the terms ousia and hypostasis were used almost interchangeably[3] and was not clarified until the First Council of Constantinople (381) after the work of Athanasius and the Cappadocians.[4]

Equivalent words to “essence” occasionally include “nature”, “substance” or “being”.

As such, we can say that the Trinitarian definition is summarised as: in the one God, there are three persons, the Father, the Son and the Holy Spirit, who share the one in the same essence.

Ousia and Hypostasis in general

These words are very poorly translated into “essence” and “person” for the sake of grappling with the doctrine of the Trinity, but it is important to bear in mind that hypostasis can be applied to any given object, whether personal or impersonal. Strictly speaking, the hypostasis is simply a concrete instance of the ousia, while the ousia provides the underlying reality that makes any given hypostasis the hypostasis it is, which includes any and all of its possible actions. 

To illustrate, consider Joseph Schooling, a pigeon and an orchid. Each is a hypostasis of his/its own essence (ousia) and his/its own essence makes each the hypostasis it is. Schooling is a human hypostasis, in that he is a concrete instance of his essence, which is humanity. Contained within the essence of humanity is everything that makes him human, which sets him apart from the pigeon and the orchid. This essence of humanity is what makes it impossible for him to photosynthesise or fly without aid – such are examples of actions that are not contained within his humanity. This is because although ousia do not act, hypostases act through their given ousia.

That is not to say that all hypostases of the same ousia are able to do what every other is able to. I am not able to swim to Olympic gold like Schooling is. However, what our shared ousia provides for me is the possibility to swim like him, which would be lacking in the pigeon or orchid.[5] However, since hypostases act and not ousia, I, as a distinct hypostasis from Schooling, act differently from him though all my different acts are also possible to him because of our shared ousia.

To recapitulate:

1. A hypostasis is a concrete and distinct individual while its ousia provides its underlying reality, which makes it the kind of hypostasis it is. Therefore, a hypostasis is inseparable from its ousia. Schooling is a distinct human individual because of his humanity.
2. Ousia do not act, only hypostases do, though every hypostasis acts in and through its given ousia, since ousia provides the necessary attributes to act. Schooling acts, not his humanity, but he acts through his humanity.

Ousia and Hypostasis in God

When speaking about God, the landscape shifts, despite retaining the same logical concepts behind ousia and hypostasis. Since we begin with the basic presupposition that God is a personal being who speaks (Gen 1:3) and interacts personally with others (Gen 1:1 – Rev 22:21), we can now translate ousia and hypostasis properly as “essence” and “person”.

Reiterating the Trinitarian formula: there are three persons in God who share the one in the same essence. Here is where it gets tricky. Earlier, I mentioned that I was of the same essence as Schooling, i.e. humanity. In that case, it could be correct to say that humanity was a species to which both Schooling and I belong. However, when speaking of God, we must be careful not to conceive of the divine essence as a “species” which the Father, Son and Spirit belong to. This is because that would simply mean that the Father, Son and Spirit are three gods the way Schooling and I are two humans. That cannot do – there is only one God and not three. This means that somehow we must confess that Father, Son and Spirit are the exact same God, while still preserving their distinctions that Scripture so clearly presents. At this juncture it is perhaps easier to say what God is not, rather than what He is.

We do so by a few steps. Firstly, as mentioned above, the essence that Father, Son and Spirit share is not a generic one, but a singular one – the very essence of the Father is the very essence of the Son is the very essence of the Spirit. This is unlike the way Schooling and I share the same human essence, since we do so generically and not singularly.

Secondly, each divine person has the whole divine essence in Himself. Neither Schooling nor I can be said to be the whole human essence in either of ourselves. However, in the person of the Father, there is the whole divine essence. In the person of the Son, there is the same whole divine essence. In the person of the Spirit, there is the same whole divine essence. This means that whatever the Father is, the Son is and whatever the Son is, the Spirit is. This also means that no one person is a part of the divine essence; rather, each has the whole divine essence in Himself.

Thirdly, the divine essence is not the reality behind the divine persons. This is where we stumble at our previous understanding of essence and persons, where essences are the underlying realities of any given persons. Neither Schooling nor I exist as necessarily as the human essence – there were countless of other human persons before either of us came into existence. Therefore, we could say that our human essence is anterior to us. We are unnecessary to it; remove both of our persons and the human essence remains. However, the same is not true of God. For as long as God exists, He has always existed as Father, Son and Spirit. Therefore, neither the divine essence nor the divine persons are anterior to the other; the divine essence and the divine persons are just as necessary and ultimate as the other (though the divine essence is indeed what ensures each divine person is divine).

Fourthly, God is simple, i.e. not made up of parts (uncompounded). This doctrine we will pick up in a later article.

Together, these four propositions protect us from thinking that ousia and hypostasis in general can be directly mapped onto our thoughts of God. These concepts still serve as valid tools to know accurate things about God, but they fail to directly explain God as He is absolutely in Himself, for our language shall forever stutter when contemplating the incomprehensible God.

Implications of essence and persons

The Trinity is not a contradiction

Contradictions arise when A is both A and A’ at the same time in the same relationship. Therefore, the Trinity would be a contradiction if God was both one and three in either essence or person. By understanding the distinction between the divine essence and the divine persons, we can therefore answer any objection to the Trinity as a contradiction: God is one in essence and three in persons, and that is no contradiction.

Inseparable operations

The main implication of confessing that Father, Son and Spirit share the one in the same essence is that Father, Son and Spirit always act inseparably (at least relative to creation), since persons act in and through their natures, while natures provide the attributes for persons to act.

In the example of Schooling and me, though we have a common human essence, we do not share the same singular essence. Therefore, he has a human mind or will separable from mine. Given that Father, Son and Spirit share the same singular essence, they share the same attributes, mind, will and power. This is why the Athanasian Creed said that though “the Father is [Attribute X], the Son is [Attribute X], the Holy Spirit is [Attribute X]”, “there are not three [Attributes X], but one [Attribute X]”. The Father is almighty, the Son is almighty, the Holy Spirit is almighty, but there are not three almighties, but one almighty. This kind of radical unity cannot be said about Schooling and me.

Therefore, although Father, Son and Spirit act distinctly because they are distinct persons, they act inseparably through the one inseparable essence that they share. We will explore this further in subsequent articles. For present purposes, simply understand that all three divine persons act inseparably through the singular attributes of the one singular and inseparable divine essence.

Conclusion

The purpose of this first article is to set the stage for further elucidation of the Trinity. By grasping the most fundamental of vocabulary of the doctrine, we now have a framework with which we can speak more precisely about the God who is both one and three.

In the next article, we will consider further the unity of God by looking in greater depth the doctrine of simplicity.