Table of Contents
- Monarchia
- One Substance
- Is the Immanent Trinity ἀρχή?
- Is the Trinity 3 Gods
Two Key Concepts Construct Trinitarian Monotheism: Monarchia and Undivided Substance
Trinitarian monotheism is fundamentally built upon two essential ideas: Monarchia and Undivided Substance.
Monarchia
In Greek, the term polytheia refers to polytheism, a concept well known in antiquity and found in the writings of authors such as Philo. However, the word monotheia, which would correspond to monotheism, does not appear in Greek literature until much later—specifically in the 14th century, during the theological debates between Gregory Palamas and Barlaam.
Modern scholars often rely on the Thesaurus Linguae Graecae, a comprehensive digital library containing approximately 95–99% of all Greek literature composed before the fall of Constantinople. When searching this vast collection, one finds that monotheia is absent from early Christian writings. Instead, the term that early Christians actually used to express the concept of monotheism was monarchia (meaning monarchy or singular rule).
Thus, rather than speaking explicitly of “monotheism” in the way we understand the term today, early Christian theologians framed their belief in the one God through the concept of Monarchia—emphasizing the singular rule and unity of God, even within the complexity of the Trinity. You can see this in Gregory of Nazianzus, particularly in Oration 29, where he lays out three options:
The three most ancient opinions concerning God are Anarchia, Polyarchia, and Monarchia. The first two are the sport of the children of Hellas, and may they continue to be so. For Anarchy is a thing without order; and the Rule of Many is factious, and thus anarchical, and thus disorderly. For both these tend to the same thing, namely disorder; and this to dissolution, for disorder is the first step to dissolution. But Monarchy is that which we hold in honour. It is, however, a Monarchy that is not limited to one Person, for it is possible for Unity if at variance with itself to come into a condition of plurality; but one which is made of an equality of Nature and a Union of mind, and an identity of motion, and a convergence of its elements to unity — a thing which is impossible to the created nature — so that though numerically distinct there is no severance of Essence. Therefore Unity having from all eternity arrived by motion at Duality, found its rest in Trinity.
Related terms such as anarchia, polyarchia, and monarchia are often translated into English as anarchy, polyarchy, and monarchy. However, these translations can be misleading because they imply political systems, while in the theological debates, the terms carry a different meaning. Gregory Palamas, for example, uses these terms not to discuss politics but to describe different concepts of divine governance:
- Anarchia: the absence of a governing principle—equivalent to atheism.
- Polyarchia: multiple governing principles—equivalent to polytheism.
- Monarchia: one governing principle—equivalent to monotheism.
Gregory explicitly associates anarchia and polyarchia with the “children of the Greeks,” meaning pagans, thereby affirming that monarchia refers to monotheism—the belief in one divine source or principle.
This use of monarchia also appears in earlier Christian debates, such as those involving Tertullian and the Modalists. Tertullian criticized the Modalists—who taught that the Father, Son, and Holy Spirit were merely different modes or manifestations of one God—by calling their position Modalistic Monarchianism. He argued that their overemphasis on preserving the monarchia (the unity of the one divine source) led them to deny any real distinctions between the persons of the Trinity. Their desire to maintain the oneness of God ironically resulted in blurring the genuine personal distinctions within the Godhead.
One Substance
However, the Monarchia alone doesn’t prove strict monotheism because the Pagans believed in 1 Monarchia too (Gnosticism believed in 1 Monarch, the Monad or the One Supreme God while also affirming many lesser divinities or emanations from the Monarch). You also must, as Gregory said above, prove the shared substance between the Trinity.
Basil of Caesarea says:
There is one God because there is one Father. But the Son is also God, and there are not two gods because the Son has identity with the Father. For I do not behold one divinity in the Father and another in the Son. Nor is one nature this and the other that. So then, in order to make clear for you the distinctness of the person, count the Father by himself and the Son by himself, but in order to avoid secession into polytheism, confess one substance in both. In this way both Sabellius falls and the Anomoian will be shattered.
Basil, Homily 24 (Against Sabellians, Arians and Anomoians).
He argues that if someone introduces two first principles, then they have introduced two gods. But as long as there is one Father and one Son, then there is still only one first principle—the Father which avoids modalism. The Son, though distinct, is from the Father, having the same essence (ousia) as Him. This is how early Christians understood monotheism: God is one because the Father is the one uncaused source (the “monarchia”), and the Son and Spirit proceed from Him con-substantially without introducing multiple first principles.
Is the Immanent Trinity ἀρχή?
The Greek word ἀρχή (archē) carries a dual meaning: it can signify both “beginning” and “rule” (the latter being the root of the word “monarchy”). This dual meaning sometimes leads to ambiguity in theological discussions about the Trinity.
Some theologians, including Gregory of Nazianzus, describe the Trinity as a “shared monarchy.” However, Gregory is consistently clear that only the Father is uncaused and eternal in the sense of being the first cause. The Son and the Spirit proceed from the Father; they are not uncaused themselves but originate from the Father as the source.
When Gregory speaks of a “shared monarchy,” he is not suggesting that all three persons of the Trinity are equally uncaused in so far as they relate to one another. Rather, he is using ἀρχή in their economical role as the One God, meaning that by virtue of their shared essence, they are equally “uncaused”, “ruler” and have equal “authority.” In this understanding, the Father, while the ultimate source and origin in the Immanent Trinity, His rule and authority are equally shared with the Son and the Spirit economically.
Is the Trinity 3 Gods?
The doctrine of the Trinity teaches that God is one divine essence in three distinct Persons: Father, Son, and Holy Spirit. This raises a natural question: if the Persons are really distinct, doesn’t that mean there are three Gods? After all, when we speak of multiple humans sharing the same nature, we’re talking about distinct beings — each with their own mind, will, and existence. So why doesn’t that same logic apply to the divine nature? The answer lies in the kind of essence God has and how it differs fundamentally from created essences like human nature.
The simple answer is that, in creation, multiple instantiations don’t share an absolute identical nature. But the Trinity does share an absolute identical nature. Therefore to say “3 God’s” is illogical.
Unlike human nature, God’s essence is not a universal and therefore is infinite, simple, and unrepeatable. Because of the type of nature that humanity has, when the universal essence is predicated upon multiple particulars, it causes the 1 human nature to be multiplied and repeated in existences meaning it results in multiple separate and individual human beings, each with a separate will and mind. In simple terms, 1 human essence, multiple existences. This is because particular instantiations are “examples” or “types” of their universal essencess. A puppy is an example of “dogness”. Peter is an example of “humanity”. Michael is an example of “angelicness”. But the 3 persons cannot be “examples” of God. That would be 3 Gods because you have 3 examples of “Godness”.
God’s nature, however, is absolutely infinite and identical to His existence (actis puris = Pure Act).
You cannot repeat or have multiple examples of “Godness” because for there to be distinct examples of “Godness” requires exactly that, a distinction. You cannot have two identical infinite beings or existences, because the very notion of “two” presupposes a real distinction — which, in turn, implies limitation. If one being differs from the other, then one must possess what the other lacks, and a truly infinite being by definition lacks nothing. Thus, multiplicity among infinite beings entails a contradiction: the infinite cannot be lacking.
Leibniz’s law is the Law of the Identity of Indiscernibles. It states:
“If two entities share all their properties, they are identical; that is, they are one and the same thing.”
In simpler terms: if you cannot find any difference between two things, then they are not actually two things at all, but a single entity referred to in different ways, like “Superman” and “Clark Kent”.
For 2 God’s, if “God A” differs from “God B,” in any essential attributes, like a distinct consciousness which “God A” posses but “God B” does not, this means one must lack something the other has (in this example, the other God’s consciousness)— but an infinite being, by definition, lacks nothing. There must be an essential attribute (or an attribute belonging to the essence) that differs “God A” from “God B”, this is we call separate existences. For example, the distinguishing essential markers for 2 humans are 2 wills, 2 consciousnesses, 2 bodies, 2 rationels etc. But, two infinite beings is a contradiction, and God’s essence cannot be multiplied (2 exisntences) across multiple instances. There is — and can only be — one infinite, necessary, indivisible being. The question then ought to be asked: “if the Trinity is 3 Gods, what essential property (or properties belonging to the essence/nature) differentiates them?” to which the obvious answer is “Nothing.” Therefore its 1 God.
What about the distibction of the 3 persons? How, then, can there be three Persons in the one God? Classical Trinitarian theology answers: the distinction among the Persons is not a division in essence, but a distinction only in relation and how they posses the essence. The Father is unbegotten, the Son is begotten, and the Spirit proceeds — these are real, eternal relations within God, not distinct existences (beings). Each Person is fully and entirely God, possessing the one undivided divine essence. There is not one-third of God in the Father, another third in the Son, etc. — the divine nature is not split among them. Rather, it is wholly and indivisibly possessed by each Person. The distinctions are who they are, not what they are. In other words, these relational attributes don’t belong to the essence but to the persons. So these can’t be used as “proof” of 2 God’s.
This is why the Trinity does not entail three Gods. The Father, Son, and Holy Spirit do not each have separate minds, wills, or centers of consciousness the way three humans do. God’s will and intellect are one, because His essence is one. The Persons are not “instances” of divinity in the way that humans instantiate human nature — because divine essence cannot be instantiated without ceasing to be infinite and simple. So while human persons multiply nature across distinct beings, divine Persons do not multiply God. The relational distinctions are real and eternal, but they do not introduce division, composition, or multiplicity in the essence of God.
In summary: the Trinity is not a contradiction or covert tritheism, because the kind of essence we are dealing with in God is categorically different from created natures. God is not one nature shared by three beings, but one undivided essence who eternally exists as three relationally distinct Persons. The key is this: distinction of Persons does not imply division of essence, and relation does not introduce multiplicity in being. That’s why Christians can say — coherently and faithfully — that the Trinity is three Persons and yet one God.
John of Damascus says:
The Deity is perfect , and without blemish in goodness, and wisdom, and power, without beginning, without end, everlasting, uncircumscribed , and in short, perfect in all things. Should we say, then, that there are many Gods, we must recognise difference among the many. For if there is no difference among them, they are one rather than many. But if there is difference among them, what becomes of the perfectness? For that which comes short of perfection, whether it be in goodness, or power, or wisdom, or time, or place, could not be God. But it is this very identity in all respects that shows that the Deity is one and not many.
Again, if there are many Gods, how can one maintain that God is uncircumscribed? For where the one would be, the other could not be.
St. John of Damascus, An Exposition of the Orthodox Faith, Book 1, Ch. 5
And this may be perceived throughout the whole of creation, but in the case of the holy and superessential and incomprehensible Trinity, far removed from everything, it is quite the reverse. For there the community and unity are observed in fact, through the co-eternity of the subsistences, and through their having the same essence and energy and will and concord of mind , and then being identical in authority and power and goodness — I do not say similar but identical — and then movement by one impulse. For there is one essence, one goodness, one power, one will, one energy, one authority, one and the same, I repeat, not three resembling each other. But the three subsistences have one and the same movement. For each one of them is related as closely to the other as to itself: that is to say that the Father, the Son, and the Holy Spirit are one in all respects, save those of not being begotten, of birth and of procession. But it is by thought that the difference is perceived. For we recognise one God: but only in the attributes of Fatherhood, Sonship, and Procession, both in respect of cause and effect and perfection of subsistence, that is, manner of existence, do we perceive difference. For with reference to the uncircumscribed Deity we cannot speak of separation in space, as we can in our own case. For the subsistences dwell in one another, in no wise confused but cleaving together, according to the word of the Lord, I am in the father, and the father in Me John 14:11: nor can one admit difference in will or judgment or energy or power or anything else whatsoever which may produce actual and absolute separation in our case. Wherefore we do not speak of three Gods, the Father, the Son, and the Holy Spirit, but rather of one God, the holy Trinity, the Son and Spirit being referred to one cause , and not compounded or coalesced according to the synæresis of Sabellius. For, as we said, they are made one not so as to commingle, but so as to cleave to each other, and they have their being in each other without any coalescence or commingling. Nor do the Son and the Spirit stand apart, nor are they sundered in essence according to the diæresis of Arias. For the Deity is undivided among things divided…
Ibid. Ch. 8
In short: What constitutes there being 1 God in light of the 3 distinct persons:
- Same Essence
- Divine Simplicity
- Identical Energies
- Perikoresis