In the last article, we saw that there were two ditches people often veer into when talking about the singularity of and plurality in God: Sabellianism and Tritheism. The former denies personal distinction(s) in God and the latter denies the unity of the persons of Godhead.
In this current article, I seek to show that there are real, personal distinctions in God even while he is simple—undivided and one. Again, in God’s unity, there are real distinctions between the divine persons of the Trinity: Father, Son, and Spirit. Remaining in orthodox trinitarianism, and more importantly, submitting to what the Bible says, the one God is triune. The Bible speaks of this one God in three distinct persons: Father, Son, and Spirit. There are true, essential distinctions of persons in this one God. The Father is not the Son or the Spirit; the Son is not the Father or the Spirit; and the Spirit is not the Father or the Son. My aim is to show that these persons really are real, distinct persons with their own distinguishing, personal properties and thus refute and deny the ancient heresy of Sabellianism—the denial of real, personal distinction in God.
The divine persons are distinct and unified. Here, distinction and unification do not trump one another, bur rather go hand-in-hand and are necessary in the “personhood” of the divine persons and the “Godness” of God. In this section, we’ll cover numerous points in regards to what a divine person is, is not, and how a divine person is distinguished.
(a) The Term, “Person”
The term, “person,” has undergone much debate throughout the history of the church. While a historical synthesis and background would be helpful, space restricts us to limit our study on the basic meaning. The term “person” ultimately indicates that “this one” is not “that one.” Hence, the term “person” signifies real distinction.
(b) What a Divine Person Is Not
Let’s begin to clarify what a divine person is not. A divine person is not a fraction of the divine essence. Because God is simple, there is no composition in God (simplicity simply means uncompounded). Consequently, a person is not parsed out as “part” of God or a “sliver” of God. Hence, a divine person is not something other than the divine essence. Therefore, a person is not secondary or additional to the divine essence as if the essence was an anterior reality or lower layer to the persons. In sum, a divine person is not something other than or different from the divine essence.
(c) The Divine Persons Therefore Hold Something in Common
Since therefore the divine persons are not additional to or severed from the divine essence, that is, they are not “other than” the divine essence, the divine persons hold something in common: the divine essence. Therefore, divine persons share real unity and are thus equal in substance—being, essence, nature, and divinity. Since the divine essence is simple (i.e., uncompounded), they are identical with reference to essence (and therefore will, power, and attributes, since God is indeed simple). In sum, the divine persons are (1) identical in essence, and so (2) are equal in deity. Hence, each person of the Godhead “possesses all that is the divine essence.” The common (i.e., shared) property of the divine persons, indicating their unity, is the undivided, self-existent, divine essence. So if the persons share they same essence, they are not distinguished by their essence (as indicated above), but rather, they are distinguished simply by relation to each other.
(d) Divine Names Indicate a Difference
When speaking of God, Augustine says, there are two manners of predication (i.e., assertion): substance (essence) and relation. Predication of substance identifies unity, and predication of relation identifies distinction.
In the Scriptures, the divine, personal names themselves tell us that there is real relation in God. The name “Father” and the name “Son” indicate real relation, for the Father is father of/to the Son, and the Son is son of the Father. The divine names identify and signify a relation, and relation simply refers to distinction and multiplicity, for one to have a “relation,” it must do so with “another.” Thus, the names “Father” and “Son” indicate opposite ends of a relation: the Father and the Son, and the Father is not the Son and the Son is not the Father, as we can tell through their relation. This indication also includes the Spirit. The Spirit is Spirit of the Father (Matt 10:20), and therefore not the Father, and the Spirit is also Spirit of the Son (Gal 4:6), and therefore not the Son. Relational predication indicated through the divine names in Scripture tells us there is real distinction(s) in God because relation “identifies someone with reference to someone else.” Thus, because the persons are identical and unified in essence, the way we can identify and distinguish divine persons, as the divine names indicate, is through only relation.
(e) Distinction by Relation of Origin
We can only “mark” or distinguish the persons by one way: how the persons relate to each other. These relations are particular relations, that is, they are relations of origin. The relations of origin denote how the divine persons relate through “source” (principle point) or origin, that is, they signify from whom a person proceeds from. Hence, for example, Y is distinct from X, because Y proceeds from X; and Z is distinct from both X and Y, because Z proceeds from both X and Y; therefore, X is not Y, and so on and so forth. In short, the relations of origin distinguish persons through eternal “source” or origin point. Put in another manner, using another term for this same concept, persons are distinguished by the divine processions, namely, the manner in which a divine person proceeds from another.
The relations of origin and divine processions are not two different ways to distinguish a person, but they are two ways of speaking about the same thing, namely, that the divine persons are distinguished by how they relate to one another, and they relate to one another by whom they proceed from, indicating their origin point (source). In shorter form, the two terms, “relations of origin” and “divine processions,” distinguish persons by indicating the origin (principle) point they eternally proceed forth from. Hence, these relations are relations of opposition (i.e., they are relations with opposite ends): origin point (source) and termination point (end)—one who acts as origin and one who proceeds.
Now, we would do well here to first indicate a few things of what the divine processions are and are not. The divine processions are internal works of God (opera Dei ad intra), more specifically, they are communications of the divine essence between the divine persons. They are intrinsic to who God is. God’s life is his life in the divine processions. The processions are not something added to his life nor are they merely something he does. These internal works whereby the persons relate to one another, namely, the divine processions, are his life. Further, since these internal works of God are eternal communications of the divine essence, they are not a production, creation, ontological beginning, or a coming into being. Hence, the terms “origin” and “source” do not imply beginning or start of something, but rather, they denote the eternal point from which a person proceeds. Hence, there is no start, no beginning, no succession, and no end of, to, and in these internal works of God in which God is.
In sum, the divine processions are intratrinitarian works wherein persons eternally relate to one another as indicated through origin, and are specifically then, communications of the divine essence. As Swain and Allen say, “the processions of the divine persons are internal to the simple and indivisible being of God. They signify the unique ways in which the one divine being of God is eternally communicated to or by each person within the fecundity that is the triune God.”
(f) Two Processions in God
As the divine names show, there are two processions (relations) in God: (1) the eternal generation (i.e., begetting) of the Son by the Father and (2) the dual procession of the Spirit by the Father with the Son. In regards to the former, the doctrine of eternal generation refers to the Father-Son relation wherein the Father eternally begets the Son and thus the Son is eternally begotten as one who is from and only from the Father. Hence, this relation shows distinction: “The Father begets or generates the Son, which puts Father and Son at opposite ends of the relation generator–generated.” In regards to the second procession, the dual procession of the Spirit refers to the Father together with the Son, as one principle, breathing out (spirating) the Spirit and thus the Spirit proceeds from both the Father and the Son. Again, this shows distinction because the Spirit stands at the opposite end of the Father and Son in this relation (and the Father and Son are already distinguished through eternal generation of the Son).
(g) Personal Properties
Because each person subsists in or has the divine essence, they share a common property—the divine essence—as we already noted. And because the persons are distinguished through relations of origin, namely, because this one proceeds from that one, we assert that a distinct person has a personal property that is “personal” to them and to them alone. Hence, relations of origin or the divine processions highlight the relational property that belongs to each person, distinguishing one from the other two. The term “personal property” coincides with the term “relations of origin” in that the relations of origin distinguish the persons, and a personal property constitutes a person as a person. In other words, because the Father is the only one who eternally begets/generates the Son and is thus father to the Son, his personal property is paternity (fatherhood) and is thus distinguished from the other two; because the Son is the only one who only proceeds (i.e., is eternally begotten/generated) from the Father and is the only son of the Father, his personal property is filiation/generation (sonship) and is thus distinguished from the other two; because the Spirit is the only one who proceeds (i.e., is spirated/breathed out) from both the Father and the Son, albeit as one principle (source/origin point), his personal property is procession and is thus distinguished from the other two.
From these personal properties, it is quite apparent that there are real, personal distinctions in God contra Sabellianism. The Father is not the Son, the Son is not the Father, and so on and so forth. These distinctions are indicated in the eternal, inner relations of origin wherein personal properties are manifest because they stand at opposite ends of a relation.
(h) Synthesis: What Is a Divine Person?
After all these points, what shall we say a divine person is? Like the first point (a), the notion of “person” has received much speculation and debate over the centuries and space forbids a deep, thorough explanation of historical deduction. Instead of doing vast analysis, I’ll pick two definitions that work together.
In his classic essay on creation’s Creator, John Webster points us to John Owen to have a solid understanding of a divine person: “[A] divine person is nothing but the divine essence, upon the account of an especial property, subsisting in an especial manner.” In other words, a person of the Godhead is the divine essence subsisting (acting/working/relating/possessing the divine essence) in a particular way.
Perhaps working from whole scale to individual/particular will be helpful for understanding, that is, starting with the broader view on the Trinity as whole, then focus on persons. Webster writes, “The triune God is one simple indivisible essence in an irreducible threefold personal modification. That is, God’s unity is characterized by modes of being in each of which the entire divine essence subsists in a particular way; this simultaneous, eternal existence in these three modes is the one divine essence.” Just a few sentences later, Webster says, “the persons are inseparable from the essence, and the essence inseparable from its threefold personal modification.” Hence, at the core, we can gather at least two things: (1) each person “possesses” or subsists fully in the divine essence, and so are really divine, and (2) a divine person of the Godhead is one who “subsists” in a particular way in the divine essence. How might we say it is particular, that is, distinguishing? For help, we look to Thomas Aquinas’ work.
A little bit of Thomas Aquinas almost always pushes our understanding further when speaking of trinitarian theology/ontology. In his treatise of Aquinas’ trinitarian theology, Gilles Emery observes that “St Thomas conceives the divine person as a subsisting relation.” In his own words, Thomas writes, “The ‘divine Person’ means relation as something subsisting (relation ut subsistens)” and elsewhere he says, “I thus affirm that a ‘person’ in God means a relation in the mode of substance …, not the substance which is the essence, but the substance qua the supposit possessing the essence.” The term “relation” is key and helpful for what we mean when we say that a person is the divine essence that subsists in a particular manner, namely, a relational one.
In sum and in an over drastically simplified manner, a divine person is (1) not additional, other than, or severed from the divine essence, but is irreducible to it and is thus God and is unified to the other two persons; (2) nevertheless, a divine person is peculiar and therefore distinctive; (3) a divine person is distinguished by and only be a particular relation, that is, relation of origin; and (4) a divine person has a personal, distinctive property, constituting them a distinct person subsisting in the divine essence.
Biblical Notions for Relations of Origin and Divine Processions
One may question the biblical evidence of the divine processions/relations of origin. There really is no stand-alone proof-text of that exhaustively encompasses the doctrine of the divine processions. This concept is drawn from patterns seen in God’s works in the economy (i.e., the created realm) copied down in the biblical text. Because God’s external works correspond to who he is in his inner works, or in Emery’s words, “God acts according to what he is in himself,” one can make dogmatic deductions about God’s inner life from the outer works of God (opera Dei ad extra).
As seen in the economy, since the Father sends the Son and with the Son sends the Spirit and is not sent himself, it tells us that he does not proceed from anyone eternally; on the other hand, since the Son is sent by the Father, it shows that he himself is generated by and only be the Father eternally; finally, since the Spirit is sent by the Father and the Son, it tells us that he himself proceeds from the Father and the Son eternally. The temporal, divine missions (sendings) reveal who God is in himself, or put differently, the divine processions constitute the divine missions. Hence, temporal missions reveal and presuppose eternal procession. With knowledge of the divine processions, distinct persons are made manifest. Nevertheless, there are some texts that indicate these internal works.
Aquinas on the Term “Procession” as a Scriptural Given
The term procession, according to Dominic Legge, drawing from Aquinas, is “drawn directly from Scripture.” Aquinas is very apt to cite texts like John 8:42, “If God were your Father, you would love me, for I proceeded forth and have come from God,” and also John 15:26: “when the Helper comes, whom I will send to you from the Father, the Spirit of truth, who proceeds from the Father, he will bear witness about me.” Hence, according to Aquinas’ exegesis (and so Augustine too), “the existence of ‘processions’ in God [are] a given, scriptural teaching: ‘In relation to God, sacred Scripture uses words which indicate procession.’” From this, we can look at two case studies of an exegetical argument of the biblical validity of eternal processions.
John 5:26: The Son’s Eternal Generation by the Father
Perhaps one of the most common “proof-texts” for the eternal generation of the Son is John 5:26: “For as the Father has life in himself, so he has granted the Son also to have life in himself.” According to Don Carson, John 5:26 makes the notion of the Son’s eternal generation “unobjectionable.” In this text, Jesus says, “For as the Father has life in himself, so he has granted the Son also to have life in himself” (John 5:26). In this, we see a couple things. First, God the Father possesses (ἔχει [echei]) aseity—has life in himself—and thus he subsists in the divine essence, in which he absolutely exists. Second, the Son also possesses aseity as the Father has life in himself. Hence, both persons are thus fully and equally God. But there is more to this, remember, “equality does not require sameness.” A distinction is made: the Father grants (ἔδωκεν [edōken]) the Son to have aseity. Given the semantic range of δίδωμι (didōmi), one can rightly read this as “the Father gives aseity” to the Son. This granting/giving is the communication of aseity—that which can only be attributed to the divine essence—to the Son, hence, the notion of eternal generation: the Son is equal to and yet distinct from the Father as indicated through an order of relation whereby the Father communicates the undivided essence to the Son—Father eternally generates the Son.
John 15:26; 16:14–15: The Spirit from the Father and the Son
In John 15:26, Jesus says of the Spirit, “when the Helper comes, whom I will send to you from the Father, the Spirit of truth, who proceeds from the Father, he will bear witness about me.” Here, we see that the Father is the principle (origin point) of the Spirit, since the Spirit proceeds from God the Father. So we clearly see that the Spirit is from the Father as one who proceeds from him. So what about the Son? First, it is interesting that Jesus calls the Spirit the “Spirit of Truth” right after he calls himself the Truth (14:6). So there must be some connection of the Spirit and the Son. Upon further reading and examination, we see something especially intriguing in John’s Gospel. In John 16:14–15, Jesus says, “He [the Spirit] will glorify me, for he will take what is mine and declare it to you. All that the Father has is mine; therefore I said that he will take what is mine and declare it to you.” The italics highlight verses like John 5:19, 30: “the Son can do nothing of his own accord, but only what he sees the Father doing. For whatever the Father does, that the Son does likewise … I can do nothing on my own.” As one begotten of the Father, the Son is the image of God (Col 1:15) and the exact representation of God (Heb 1:3) and therefore, has what the Father has. And so, as Jesus says, all that the Father does, the Son does likewise, which would include breathing out the Spirit together with the Father. Hence, commenting on John 16, Aquinas says, “so if the Father gives his essence to the Holy Spirit, the Son must also do so. For this reason he [Jesus] says, all that the Father has is mine. And if the Holy Spirit receives from the Father, he will also receive from the Son. And for this reason, he says, therefore I said that he will receive from me and declare it to you, for according as he receives from me, so he will show you.” Therefore, “the Spirit shows among us what he (eternally) receives, namely, essence from the Father and Son.”
Conclusion: So What?
As shown above, there are true, personal distinctions in God: Father, Son, and Spirit. There are multiple (three) persons in God that are truly unified—on the virtue of their shared essence—and they are really distinct—as indicated in their relations of origin. So we now come to perhaps one of the most pressing questions: Why does this even matter that we affirm multiplicity of persons in God? The answer, according to Thomas Aquinas, covers at least two grounds:
The knowledge of the divine persons was necessary to us on two grounds. The first is to enable us to think rightly on the subject of the creation of things. For by maintaining that God made everything through the Word we avoid the error of those who held that God’s nature necessarily compelled him to create things. By affirming that there is in him the procession of Love [the Spirit], we show that he made creatures, not because he needed them nor because of any reason outside him, but from Love of his own goodness…. The second reason, and the principle one, is to give us a true notion of the salvation of mankind, a salvation accomplished by the Son who became flesh and by the gift of the Holy Spirit.
So, affirming the multiplicity of persons in God, according to Aquinas, helps us realize that we were not created because God needs us, as if he was “alone” and needed to “add” to himself. Because the divine processions, especially the procession of the Holy Spirit, which is often called the procession of Love, show us that God is complete, perfect, and fully satisfied in himself, the outward movement of creating the universe was a sheer act of love because it was unnecessary and since the universe was created by his Word and Spirit, it was “out of love.” Second, and this is of great importance, affirming the multiplicity and distinction of persons matters because salvation is on the line. Because only God can save, and we are to confess that the Son became man on our behalf and that the Spirit really works for us and for our salvation, we must confess and call upon the triune God (John 17:3). So these matters—trinitarian theology—are not mere thought or analysis (as if God could be merely analyzed), but they are pertinent to our right understanding of God, creatures, and saving faith. We affirm and confess, then, that God is triune: God is one, with reference to essence, and God is one in three distinct persons: God the Father, God the Son, and God the Spirit.
In the next three articles in the systematic theology category, we will cover, in depth, each person of the Trinity, their relation to the other two persons, and their personal properties.
 John Webster, God Without Measure: Working Papers in Christian Theology (T&T Clark Bloomsbury: London, 2015), 1:88.
 Augustine, De Trin. 5.1.3–8.
 Swain, “Divine Trinity,” 95.
 Scott R. Swain and Michael Allen, “The Obedience of the Eternal Son,” in IJST 15 no. 2 (2013): 122.
 Fred Sanders, The Triune God, New Studies in Dogmatics 2 (Grand Rapids: Zondervan, 2017), 131.
 Scott R. Swain, “Divine Trinity,” in Christian Dogmatics: Reformed Theology for the Church Catholic ed. Michael Allen and Scott R Swain (Grand Rapids: Baker Academic, 2016), 98.
 John Owen, A brief Declaration and Vindication of the Doctrine of the Holy Trinity, 407, quoted in Webster, God without Measure, 1:87.
 Webster, God without Measure, 1:87.
 Ibid., 1:87.
 Gilles Emery, The Trinitarian Theology of St Thomas Aquinas (London: OUP, 2010), 103.
 Thomas Aquinas, Summa Theologica, 1.29.a4, quoted in Emery, The Trinitarian Theology of St Thomas Aquinas, 116.
 Thomas Aquinas, I Sentences, 23.1.3, quoted in Emery, The Trinitarian Theology of St Thomas Aquinas, 117n75.
 I use the term “exists” drawing from Emery, The Trinitarian Theology of St Thomas Aquinas, 106.
 Gilles Emery, The Trinity: An Introduction to Catholic Doctrine on the Triune God, trans. Matthew Levering (Washington DC: Catholic University of America Press, 2011), 161.
 For a helpful analysis of this insight on the relation of the immanent Trinity and the economic Trinity, see Andreas J. Köstenberger and Scott R. Swain, Father, Son and Spirit: The Trinity and John's Gospel, New Studies in Biblical Theology (Downers Grove, IL: InterVarsity Press Academic, 2008), 179–185 esp. 179–180.
 Dominic Legge, The Trinitarian Christology of St Thomas Aquinas (London: OUP, 2017), 15.
 Christopher R. J. Holmes, The Holy Spirit, New Studies in Dogmatics 1 (Grand Rapids: Zondervan, 2015), 71–72.
 Emery, The Trinitarian Theology of St Thomas Aquinas, 52, Aquinas, ST, 1.27.1.
 D. A. Carson, The Gospel according to John, Pillar New Testament Commentary (Grand Rapids: Eerdmans, 1991), 257.
 R. Michael Allen, Justification and the Gospel: Understanding the Contexts and Controversies (Grand Rapids: Baker Academic, 2013), 78.
 For a helpful discussion on this text, see Webster, God without Measure, 1:25.
 Thomas Aquinas, Commentary on John, 2115, 3:146–147 quoted in Holmes, The Holy Spirit, 99.
 Holmes, The Holy Spirit, 99.
 Thomas Aquinas, Summa Theologica, 1a.32.1, ad 3.