THE PREMIER CASE AGAINST UNITARIANISM:

Why the Father Alone Being “God” Cannot Sustain the Biblical Evidence

Q. 48: Is God a Self or Personally Simple?

I. THE “CREATURELY IDENTITY” PROBLEM

In first-order logic or basic set theory, “=” can and often denotes strict, numerical identity. In a more technical sense, “=” denotes the identity relation (since it’s not purely a numerical notion), meaning that both sides name the very same object (typically in every respect). This means:

  • Reflexivity: x = x
  • Symmetry: If x = y, then y = x
  • Transitivity: If x = y and y = z, then x = z
  • Leibniz’s Law: If x = y, then any property of x is a property of y, and vice versa…

Such properties make sense for finite or composite objects, like people, numbers, or sets. For example, if “Alice = the person who wrote this letter,” then no second individual named Bob could also be “the person who wrote this letter” unless Bob literally is Alice in every respect. In a theological context, we distinguish “creaturely” identity claims from other forms of identification or participation (including phenomenological approaches to identity). For our purposes here we’re highlighting the more strict logical senses like number or equivalence relations. So, to be more specific, if someone says “the Father = God” in this same strict, exclusive sense, then “Father” and “God” refer to exactly the same object. If we also say “the Son = God,” transitivity forces “the Son = the Father,” which contradicts the clear biblical portrait that the Father and Son remain personally distinct.

Classical (orthodox) Christian theology (Nicene or SSGO) avoids this (“creaturely” strictness) problem by recognizing that God is infinite, noncomposite, uniquely incomparable, and capable of existing as three distinct “whos” (Father, Son, Spirit) in one “what” (the one divine essence). Thus, “Father = God” in a Trinitarian sense means “the Father fully possesses the single divine essence,” not that the Son or Spirit are excluded from it. Imposing a finite or “creaturely” identity scheme on the transcendent God inevitably flattens His infinite nature into a single finite entity, and orthodox tradition has always denied such flattening.

[Side Note] In Traditional Christianity, the understanding of God differs starkly from Unitarianism in three major ways:

  • God Is God’s Own Principle: Nothing precedes or causes God; He is uncaused, self-subsistent, and “simple,” meaning He has no parts or external composition.
  • Not Merely One Self: The same God is understood as three Persons in eternal relationship, not a solitary monad.
  • Creator vs. Creature: We must not treat God as if He were merely one item in the set of existing things. God transcends all categories.

Thus, when Christian theologians say God is His own ordering principle, they emphasize that only in God do essence and existence coincide without contingency. Yet God is also tri-personal, so He is not just a single “self” among many, but a living, personal, super-essential, super-abundant, perichoretic communion who is also the source of all that exists. [Side note over]

II. HOW UNITARIANISM NECESSARILY EXCLUDES THE SON AND SPIRIT

In “strict” or “biblical” Unitarianism, only the Father is truly God. That means if the Son were also “God” in the same sense, He would be identical to the Father, erasing their distinctness. Formally:

  • Let F = “the Father.”
  • Let G = “God.”
  • A strict unitarian says F = G, so all properties of G belong exclusively to F.
  • Because Scripture insists the Son is not the Father, the Son cannot also be G without forcing “the Son = the Father” via transitivity.

Hence, unitarianism either demotes the Son to a lesser, created being or merges Him with the Father (modalism). Classical Trinitarianism rejects both extremes by affirming that one infinite essence subsists fully in the Father, Son, and Spirit, distinguishing them by “begottenness” or “procession” (marking who They are, not what They are). I have done extensive work elsewhere showing how this distinction works in a relational context (see: https://robertdryer.com/defending-divine-simplicity/).

III. “WHAT WE’D EXPECT” LIST IF UNITARIANISM WERE TRUE

If unitarianism genuinely reflected the Scriptures and the earliest Christian faith, we would see all of the following:

  1. Exclusive Reference to the Father as “God”

We would not find texts explicitly calling Jesus “God,” such as John 1:1 (“the Word was God”), John 20:28 (“My Lord and my God”), Hebrews 1:8 (“Your throne, O God”), or Titus 2:13.

  1. No Worship of Jesus or the Spirit

We would not see prayers, doxologies, or worship directed to Christ or the Spirit in the same way as the Father.

  1. No Triadic Passages

Sayings like “baptize in the name of the Father and of the Son and of the Holy Spirit” (Matthew 28:19) or “the grace of the Lord Jesus Christ and the love of God and the fellowship of the Holy Spirit” (2 Corinthians 13:14) would be inexplicable.

  1. No Early Creedal Assertions

The Church would not need to defend the Son’s equality with the Father, as we see in the Nicene Creed (God from God, Light from Light, true God from true God).

  1. The Holy Spirit Depicted Merely as an “It”

Unitarianism would treat the Spirit as an impersonal force, yet Acts 5:3-4 calls lying to the Spirit “lying to God,” showing He is a divine Person.

Scripture and early Church tradition run directly against these expectations. Indeed, the New Testament, archaeological findings of Jesus-worship (like the Eucharist) and the Megiddo Mosaic (which refers to Jesus as God in an ancient art inscription), and the creeds all indicate the opposite. Here are six more scriptural examples (beyond the ones mentioned) that show Jesus or the Spirit receiving divine worship or status:

  • Ephesians 1:21-22: Christ is exalted above all names and powers.
  • John 5:23: All should honor the Son just as they honor the Father.
  • Philippians 2:9-11: Every knee bows to Jesus, fulfilling Isaiah’s YHWH text.
  • Revelation 5:13-14: All creation worships the One on the throne and the Lamb together.
  • 1 Corinthians 12:4-6: Spirit, Lord (Jesus), and God (Father) co-mentioned in divine work.
  • John 14:16-17: The Spirit is sent as “another Helper,” personally continuing Jesus’ divine presence.

As we see, unitarian expectations do not align with the biblical and historical record or with concrete examples. Scripture repeatedly calls Jesus “God,” gives Him worship, and treats the Spirit as fully divine.

IV. THE CONTINUATION OF THE SEPTUAGINT TRADITION, UNDERMINING UNITARIANISM

“Κύριος (Kyrios)” (Lord) for YHWH and Its Application to Jesus

The Hebrew Bible’s divine name YHWH was rendered “Κύριος (Kyrios)” in the Greek Septuagint (LXX). The New Testament continues this usage by boldly applying “Κύριος (Kyrios)” to Jesus, linking Him directly to Israel’s God:

  • Philippians 2:9-11: Every knee bows to Jesus, echoing Isaiah 45:23 (YHWH is the one to whom every knee bows).
  • Romans 10:9-13: Confessing “Jesus is Lord” saves, referencing Joel 2:32, which speaks of calling on YHWH’s name.
  • Acts 2:34-36: Peter cites Psalm 110:1 (“The LORD said to my Lord”) and proclaims Jesus as this enthroned Κύριος (Kyrios).

Meanwhile, “Θεός (Theos)” is most often used for “God” when referring to the Father. A naive reading might assume “the Father alone is God,” ignoring that “Κύριος (Kyrios)” was precisely how YHWH was rendered in the LXX (the main Greek Bible before the New Testament). By calling Jesus “Lord” in that same “YHWH sense,” the New Testament shows He shares the Father’s divine identity, yet is a distinct Person.***

If strict Unitarianism were true, we would not expect the New Testament to preserve or expand on the LXX tradition of “YHWH = Κύριος (Kyrios)” and then apply it to Jesus. Yet the New Testament does precisely that, indicating early Christians saw no contradiction in affirming the Father as “Θεός (Theos)” (God) and the Son as “Κύριος (Kyrios)” (YHWH incarnate). This breaks unitarian exclusivity, showing Jesus to be co-identified with the one God, not the same Person as the Father.

(keep this in mind as Unitarians will deny premise #3 below.)

V. A FORMAL CONTRADICTION?: A REFUTATION OF STRICT UNITARIANISM

We can summarize a logical argument against Unitarianism like this:

  1. Monotheism: There is one unique divine essence (Deuteronomy 6:4).
  2. Unitarian Exclusive Claim: “Only the Father is God,” so if any other Person “is God,” that Person must be the Father.
  3. New Testament Son-Deity: Numerous passages call Jesus “God” (John 1:1, John 20:28, Hebrews 1:8, Titus 2:13) or apply YHWH’s own title, “Lord,” to Him.
  4. Distinct Persons: The Father and Son are separate Persons in Scripture.
  5. Law of Transitivity: If X = Y and Z = Y, then X = Z.

Conclusion: From (2) and (3), if Father = God and Son = God in the same strict sense, then Father = Son. But from (4), the Father is not the Son. That is a contradiction. Therefore, unitarianism must deny either the Son’s real deity or the Father-Son distinction, both of which collide with the biblical record and early Christian testimony.

In short, unitarianism claims “Father = God” and denies “Son = God,” yet Scripture says both are God and distinct Persons. Logic reveals this as a contradiction.

VI. UNITARIANISM COLLAPSES, TRINITARIANISM REMAINS

The evidence for Christ’s full deity (and the Spirit’s divinity), alongside biblical monotheism and real distinctions among Father, Son, and Spirit, is irreconcilable with strict unitarianism. Unitarianism either relegates the Son to a lesser creature or merges Him with the Father-neither aligns with robust scriptural data or the earliest Church doctrine (John 16:13).

Trinitarian theology resolves these tensions by rejecting a finite approach to “the Father = God.” Instead, it affirms that an infinite, noncomposite God can be fully possessed by multiple Persons:

  • The Father is “God,” the unbegotten source.
  • The Son is “Lord” (YHWH incarnate), also called “God” in key texts, co-equal but begotten.
  • The Spirit is personal, fully divine, proceeding from the Father (and the Son in Western tradition), as seen in Acts 5:3-4.

Thus, the New Testament’s usage of “Κύριος (Kyrios)” from the LXX for Jesus and “Θεός (Theos)” for the Father, under one divine essence, fits a tri-personal concept of God, not an exclusively unitarian one. Strict Unitarianism fails to integrate this biblical evidence and basic logical principles while maintaining the Father, Son, and Spirit in proper tension. Trinitarianism remains the only consistent viewpoint that upholds the oneness of God, the full deity of the Son and Spirit, and their personal distinction, in line with both the LXX tradition and the New Testament.

VII. GOD AS A PERSONAL SIMPLE REALITY (RATHER THAN A “SELF”)

A. Having established in the earlier sections (I through VI) that (1) strict unitarianism collapses under the weight of biblical evidence, (2) the Son and Spirit cannot be demoted or merged without contradicting Scripture, and (3) God’s infinite essence can be fully possessed by multiple Persons, we now face a deeper question: How does this tri-personal, indivisible God avoid being just one “self” among many? In other words, if God is not a single unitarian subject, does that make Him multiple “selves” or an impersonal abstraction? The short answer, drawing on all prior insights, is that God remains personally simple—not a solitary “self,” but rather an eternal communion of Persons (Father, Son, Spirit) in one, unified divine essence.

We have seen in Section I that unitarianism fails if we take God as a finite, “creaturely” identity. We have noted in Section II that insisting “the Father alone is God” excludes or collapses the Son and Spirit. In Section III, we imagined what the Bible and early tradition would look like if only the Father were God—and found that Scripture and history show otherwise. Section IV emphasized how the New Testament continues the Septuagint (LXX) pattern of calling God “Κύριος (Kyrios),” then applies that same “YHWH” title to Jesus, making Christ co-identified with the one God. Section V’s formal contradiction demonstrated that unitarianism cannot maintain both “the Father alone is God” and “the Son is also God” yet distinct. Section VI concluded that only a Trinitarian view, acknowledging an infinite reality shared by the Father, Son, and Spirit, avoids these pitfalls.

However, one final clarifying point remains: we must not reduce God to a solitary “self,” as if He were one more personal agent among creatures. Instead, classical orthodoxy describes God as a personal simple reality: three distinct “Whos” in one simple “What.” The following explains why this matters and how it addresses potential unitarian objections about “multiple selves” or “a single self.”

B. Ambiguity of the Term “Self”

Unitarianism capitalizes on the confusion arising when we treat God as if He were simply one more subject in the universe—an individualized self. Yet the Christian tradition uses ὑπόστασις (hypostasis) or πρόσωπον (prosōpon) to describe the divine Persons, indicating that each Person is the undivided divine essence, without separating into discrete, finite centers of consciousness.

C. Emphasizing Simplicity and Personhood Together

Earlier sections (particularly IV and VI) clarified that the Father, Son, and Spirit share one infinite essence. This means there is no composition of “parts” or “selves.” Each Person is a subsistence of the same indivisible Godhead. The idea that “God is simple” is integral: God’s Personhood is not layered on as an extra piece but is intrinsic to His eternal being.

D. Relational Ontology

Sections III and V hinted at the significance of the Holy Spirit’s personal actions and the Son’s co-deity, showing that God’s inner life is already relational. This defies any suggestion that God must be a single subject who looks outward to creation for relationship. Instead, the one divine essence internally comprises eternal relations—Father begetting the Son, Son being begotten, and Spirit proceeding—without fragmenting God into separate “selves.”

E. Strengthening the Unitarian Critique

If God were a solitary “self,” He could not be both utterly self-sufficient and eternally loving apart from creation. A unitarian framework either denies God’s fullness of love until creation occurs or collapses all relational distinctions (leading to modalism). By contrast, Trinitarianism explains how God’s personal reality is entirely self-contained and eternally actualized among Father, Son, and Spirit, requiring no external referent for God to be love.

Earlier we underscored and here we put it all together that God is neither a single “self” (the unitarian error) nor a composite of three partly divine individuals. Instead, God is a personal simple reality: one infinite essence, three eternally relational Persons. This framework dissolves the major unitarian objections by showing that the unity of God is preserved by divine simplicity and the relational fullness of the Father, Son, and Spirit, while never lapsing into creaturely notions of multiple “selves.”

Conclusion

In the end, strict Unitarianism cannot account for the wide range of biblical and historical data. The Old Testament’s monotheism is deepened in the New Testament by revealing one God in Father, Son, and Spirit-a tri-personal reality that honors both the oneness of essence and the plurality of distinct Persons. By applying YHWH’s own title “Lord” (Kyrios) to Jesus, the New Testament shows that divinity is not restricted solely to the Father. Meanwhile, standard identity logic tells us that if the Father alone is “God,” then Christ cannot also be called God without collapsing His Person into the Father-yet Scripture consistently treats the Father and Son as truly distinct. Only a Trinitarian framework, which treats God as an infinite essence fully possessed by the Father, Son, and Spirit, can coherently integrate every strand of evidence: the Father’s primacy, the Son’s full deity, the Spirit’s personhood, and the unity of the one God of Israel. In this way, Trinitarian theology preserves biblical monotheism, honors the Son and Spirit’s deity, and remains faithful to both reason and revelation, in a way that strict Unitarianism does not.

Unitarians will never agree, but hopefully honest people can see its weaknesses and understand better how we get unity in Trinity and Trinity and unity from an orthodox and classical perspective. Ultimately, the Father, Son, and Holy Spirit, in their eternal self-giving and receiving, perfectly embody the Oneness of God. Their mutual exchange is the unique divine love that God is, for in God, to give is to fully receive, and to receive is to fully give.

*** Note

According to a deeply informed Catholic tradition (drawing on sources like the Catechism, the Councils, and Thomistic theology), a divine Person can be succinctly defined as a “distinct subsistence of the one divine essence”-that is, someone (Father, Son, or Spirit) who fully possesses the one, indivisible Godhead but is personally distinct through a relationship of origin (unbegotten, begotten, or proceeding). This definition emphasizes that there is only one divine essence or nature, yet three real “Who’s,” each wholly and irreducibly God.

In SSGO (Self-Standing Givenness Ontology) terms, the equivalent concept would be “a self-standing relational mode of the single divine essence.” Each Person (Father, Son, Spirit) is the entire infinite reality of God, viewed under a unique relational vantage (unbegotten, begotten, proceeding), without partitioning or dividing God’s unity. The Person is “who” God is from that distinct vantage, while the “what” is the one undivided essence (within a relational context).

P.S. I ran out of space. But if there was more time and room I would have mentioned more about these notables explicitly: the emphasis on how the Holy Spirit’s personal agency (e.g., interceding, teaching, guiding) conflicts with the unitarian tendency to treat the Spirit as an impersonal force or “presence,” as well as an explicit mention of Jesus’ repeated “I AM” statements (John’s Gospel) linking Him directly to YHWH (Exodus 3:14 and Isaiah’s use of I AM statement in the Septuigent). But on the whole, the argument above covers the key difficulties for Unitarianism and gives a good contrast to Trinitarianism. God is Personally Simple not a self. Fin.

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