Trinity and Open Theism: Two Errors in Mirror Image

Why Unitarians Should Reject Open Theism on the Same Grounds They Reject Trinitarianism

A Critique & Reproof by Tom Raddatz

Introduction: The Right Diagnosis, the Wrong Prescription

Biblical Unitarians are not wrong to reject Trinitarianism. The critique is well-founded: Trinitarianism imports Greek philosophical categories — substance, hypostasis, essence, persons — that Scripture never uses to define God. It reads identity into texts that teach agency. It silences clear declarations of subordination with speculative ontological constructs. It forces the text to answer questions the text was never asking. When you press a Trinitarian to show you where Scripture declares that Jesus is the second person of a co-equal, co-eternal triune Godhead — not merely examples that might be interpreted that way, but direct declarations — the silence is deafening.

This is a legitimate and devastating critique. It should be pressed. It should never be abandoned.

But here is the question that must be asked with equal honesty: Why do so many Biblical Unitarians apply this rigorous standard to Trinitarianism and then set it down when they encounter Open Theism?

Open Theism — the doctrine that God does not exhaustively foreknow the free choices of human beings — is gaining traction in some Biblical Unitarian circles. It appeals because it seems to honor human freedom and genuine divine relationship. It sounds humble and relational. It appears to take seriously those passages where God responds, relents, or reacts to human decisions.

But Open Theism, examined carefully, commits every interpretational error that Biblical Unitarians — rightly — condemn in Trinitarianism. It is the mirror error: the same methodology, the same philosophical intrusion, the same silencing of explicit declarations in favor of inferred conclusions from selected examples.

This is not a minor inconsistency. It strikes at the root of biblical integrity. You cannot wield the standard against Trinitarianism and then refuse to be weighed by it yourself.

1. The Standard That Exposes Both

As I have argued in many of my writings, the critique of Trinitarianism that Biblical Unitarians should deploy is this:

• For any doctrine to be biblical, it must be more than an inference from examples. It must be at least named, proclaimed, confessed, explained, exemplified, and/or commanded in Scripture.
• The Bible never declares that God is a Trinity. It offers texts that Trinitarians interpret as pointing that direction. But the declaration itself — the direct statement of the doctrine — is absent.
• When Trinitarianism encounters texts that plainly teach the opposite — such as Jesus saying “the Father is greater than I” (John 14:28), or “my God and your God” (John 20:17) — it does not accept them at face value. It reinterprets them through its philosophical framework, subordinating the plain sense to the system.
• When challenged to produce a verse where any prophet, apostle, or the Lord himself proclaimed a triune God, Trinitarianism cannot answer. It offers only interpretational inferences.

This is the standard. Now, let’s see what happens when we apply it to Open Theism.

• The Bible never declares that God’s foreknowledge is limited by future human choices. It offers texts that Open Theists interpret as pointing that direction.
• The Bible does the opposite: it repeatedly declares, exemplifies, proclaims, explains, and confirms exhaustive divine foreknowledge as a mark of God’s uniqueness (Isaiah 46:9–10; Acts 15:18; Psalm 139:4,16).
• When Open Theism encounters these explicit declarations, it does not accept them at face value. It reinterprets them through its philosophical framework — specifically, through libertarian free will — subordinating the plain sense to the system.
• When challenged to produce a verse where any prophet, apostle, or the Lord himself proclaimed that God does not know what free creatures will choose, Open Theism cannot answer. It offers only interpretational inferences.

The methodology is identical. The error is the same. Only the doctrine being smuggled in has changed.

2. What Scripture Actually Declares About Foreknowledge

As Unitarians, we know full well that “God is one He” is not merely inferred; it is commanded. Likewise, foreknowledge is not merely inferred or read between the lines. Scripture goes out of its way to name it, declare it, and make it the very basis of God’s superiority over every false god.

Declared as a Divine Attribute

Isaiah 46:9–10 — “I am God, and there is no other… declaring the end from the beginning and from ancient times things not yet done.” This is not incidental. God identifies exhaustive foreknowledge as the marker of His uniqueness. It is the very thing that distinguishes Him from what is not God.

Acts 15:18 — “Known to God from eternity are all His works.” Not most. Not the ones He predetermined. All of them.

Isaiah 41:21–23 — God challenges the false gods to declare the future as proof of deity. The ability to foreknow is here presented as a test of true divinity. Open Theism, by limiting this attribute, actually moves God toward the category of the false gods He is contrasting Himself with.

Psalm 139:4,16 — “Before a word is on my tongue you, Lord, know it completely… all the days ordained for me were written in your book before one of them came to be.” Every word. Every day. Before they exist.

Demonstrated in Prophecies That Required Foreknowing Free Choices

These are not vague poetic statements. God demonstrated exhaustive foreknowledge by naming specific individuals and their free decisions centuries before they lived:

• Cyrus of Persia (Isaiah 44:28; 45:1) — Named by name approximately 150 years before his birth, with his specific act of releasing Israel and funding the temple described. Cyrus was a pagan king whose decisions were entirely his own. How does Open Theism account for this?
• Josiah (1 Kings 13:2) — Named approximately 300 years before his birth, with specific actions against idolatry described in detail. His choices were free choices. God foreknew them anyway.
• Judas’s betrayal (Psalm 41:9; Acts 1:16) — Peter declares that Judas’s betrayal was something “which the Holy Spirit spoke beforehand.” Acts 2:23 makes the same point about the crucifixion as a whole: “delivered up according to the definite plan and foreknowledge of God.” If God did not foreknow Peter’s denial or Judas’s betrayal, Acts 2:23 has no foundation. (See also Zechariah 11:13 & Matthew 27:3-10)

Try as they may, an Open Theist has no good answer for these texts any more than Trinitarians claim they have “good answers” to the shema. They can only attempt to reframe them, which is exactly what Trinitarians do to John 14:28 (“the Father is greater than I”).

3. Ezekiel 18: The Bible’s Own Explanation of Divine Responsiveness

Unitarians understand that Trinitarianism’s most appealing feature is those passages where Jesus appears to do ‘God-things’ — texts Trinitarians use to justify an entire theology built on false dilemmas the text itself does not create. Similarly, Open Theism’s most appealing feature — and its greatest vulnerability — is its claim to explain why God appears to respond and react to human decisions. Passages where God ‘relents,’ ‘repents,’ or changes course seem on the surface to support the idea that God did not know what humans would do. Open Theists lean heavily on these passages. This is the same technique that Trinitarians use in their proof-texting, when the texts they rely on do not extend to the reach that they assume. That is called eisegesis. Unitarians despise it when Trinitarians do it, but embrace it when they want to justify Open Theism.

But Scripture does not leave us to speculate about why God responds this way. It explains it directly. And the explanation has nothing to do with divine ignorance.

Ezekiel 18: God’s Responsiveness Explained

Ezekiel 18 is not a peripheral passage. It is God’s own defense of His ways in response to the charge that His dealings with Israel are unfair. The entire chapter is an extended explanation of why God responds differently to the same person at different times.

Verse 21: “But if a wicked person turns away from all his sins that he has committed and keeps all my statutes and does what is just and right, he shall surely live; he shall not die.”

Verse 24: “But when a righteous person turns away from his righteousness and does injustice… none of the righteous deeds that he has done shall be remembered.”

Verse 30: “Therefore I will judge you, O house of Israel, every one according to his ways, declares the Lord God.”

The point of this chapter is not that God is uncertain about outcomes. The point is that God is consistent in character. He deals with every person according to where they are at the time of judgment. His responsiveness is not the product of ignorance — it is the expression of His unwavering holy nature applied consistently to every moral situation.

God’s “openness” in responding to human repentance and rebellion is not about what He does not know. It is about who He is. This type of interpretation compares interpretationally to how Trinitarians change God’s identity from one “He” to one substance.

The Open Theist Hijack of This Passage

Open Theists would likely read Ezekiel 18:23 — “Do I take any pleasure in the death of the wicked? Rather, am I not pleased when they turn from their ways and live?” — as evidence that God is genuinely open to outcomes, waiting to see whether the wicked will repent.

But this is exactly the same mistake Trinitarians make when they take John 10:30 (“I and the Father are one”) and import ontological identity from it when the context is about unified purpose and agency. Both moves import a philosophical conclusion — divine limitation in one case, divine identity in the other — from a text that is making an entirely different point.

Ezekiel 18:23 is about God’s moral desire, not His epistemic state. The chapter is God defending His consistent justice, not God confessing uncertainty. A parent who has already seen the outcome of their child’s choices can still genuinely desire that the child had chosen differently. Desire and foreknowledge are not in conflict. The Open Theist reading requires a philosophical prior commitment before the text yields it.

Furthermore, the context of Ezekiel itself destroys the Open Theist reading: the same book contains detailed prophecies of what Israel will do — including their specific failures and eventual restoration. God is not uncertain about these outcomes while defending His consistent fairness in chapter 18.

4. The Parallel Errors Side by Side

The following parallel is not rhetorical. It reflects a genuine methodological identity between the two systems:

What Is Declared vs. What Is Only Inferred

• Trinitarianism: Scripture declares God is One and that Jesus acts as God’s sent agent. Trinitarianism infers from select texts that Jesus is a second divine person. The declaration is against them; the inference is all they have.
• Open Theism: Scripture declares God foreknows exhaustively. Open Theism infers from select texts that God lacks knowledge of future free choices. The declaration is against them; the inference is all they have.

How Counter-Texts Are Handled

• Trinitarianism: John 14:28 (“the Father is greater than I”) is reinterpreted through the lens of Christ’s “human nature,” not accepted at face value.
• Open Theism: Isaiah 46:9–10 and Acts 15:18 are reinterpreted through the lens of divine condescension or general providence, not accepted at face value.

The Philosophical Import

• Trinitarianism: Neoplatonic categories of essence and substance are imported to explain the God–Christ relationship, categories the Bible never uses.
• Open Theism: Enlightenment-derived libertarian free will philosophy is imported to explain the God–human relationship, a framework the Bible never explicitly uses to limit divine knowledge.

The Manufactured Problem

• Trinitarianism: Creates the problem “How can a mere man atone for sin?” then solves it by making Jesus God — bypassing Romans 5:17–19 which explicitly answers that a man reverses what a man lost.
• Open Theism: Creates the problem “How can love be genuine if God already knows the outcome?” then solves it by limiting God’s knowledge — bypassing the biblical testimony that God foreknew and orchestrated events while humans remained fully responsible agents (Acts 2:23).

The Exemplified vs. the Declared

This is the most decisive point and it deserves to stand alone:

• Trinitarianism at best finds texts that might exemplify a multi-personal God, until the biblical explanations of agency are brought to bear on those examples. There are no counter-examples of a prophet or apostle proclaiming a Trinity.
• Open Theism at best finds texts that might exemplify divine ignorance, until the biblical explanations of anthropomorphism, condescension, and covenantal confirmation are brought to bear on those examples. But Open Theism has an additional problem: there are decisive counter-examples — Cyrus, Josiah, Judas — that require foreknowledge of specific free choices.

Open Theism faces the same problem Trinitarianism faces: prophetic and declarative texts that directly falsify its central inference. The difference is not in the number of problems, but in the type: Trinitarianism has to reinterpret texts about human agency, while Open Theism has to reinterpret texts that God Himself presents as proof of His unique divinity.

5. The Foreknowledge Texts Open Theism Cannot Answer

The following is not an exhaustive list. It is a selection of the passages that most directly and specifically falsify Open Theism’s central claim. Each represents a case where God demonstrated foreknowledge of a specific individual’s free choice, or declared foreknowledge as His defining attribute:

• Deuteronomy 31:16–21 — Before Israel had entered the land, God told Moses in precise detail exactly how Israel would rebel after his death: what they would do, why, and what the consequences would be. This is not a general warning. It is a specific, sequenced account of future free decisions made by millions of people over many generations.
• Genesis 15:13–16 — God told Abraham that his descendants would be strangers in a foreign land for 400 years, enslaved and oppressed, and then brought out. This required foreknowing the decisions of Egyptian rulers, Israelite generations, and the timing of the Amorites’ sin — none of whom yet existed.
• Romans 4:17 combined with Romans 8:29–30 — God “calls things that are not as though they were” and “foreknew” those whom He also predestined, called, justified, and glorified. The entire chain of salvation depends on foreknowledge being real and exhaustive.
• Exodus 4:14 — God told Moses that Aaron was already on his way to meet him — before Moses had told Aaron anything. In Young’s Literal Translation: “lo, he is coming out to meet thee.” This is God speaking of a future event as already in progress, based not on probability but on certain knowledge.

None of these texts are ambiguous. None of them require a philosophical framework to yield their plain meaning. They simply require reading what is there.

6. A Direct Challenge

The challenge offered against Trinitarianism is fair, devastating, and must be upheld. Here it is:

Show us where any prophet, apostle, or the Lord himself named, proclaimed, confessed, explained, exemplified, or commanded the doctrine of the Trinity.

Trinitarianism cannot meet this challenge. The doctrine lives entirely on inference and importation.

Now here is the same challenge applied to Open Theism, and it must be answered with equal honesty:

Show us where any prophet, apostle, or the Lord himself named, proclaimed, confessed, explained, exemplified, or commanded the doctrine that God does not foreknow the free choices of human beings.

It is not commanded. It is not proclaimed. Not anywhere.

Open Theism cannot meet this challenge either. Its doctrine also lives on inference and importation.

God’s foreknowledge is proclaimed (Isaiah 46:10), explained (Psalm 139:4,16), confessed in the apostolic record (Acts 2:23; Romans 8:29-30), and commanded — faith itself, defined as hypostasis, the substance of things not yet seen (Hebrews 11:1), is the creaturely correspondent to God’s foreknowledge, and is non-negotiable (Hebrews 11:6).

Faith is not passive reliance on a God who is doing His best. Scripture defines faith as hypostasis — substance, underlying reality — the treatment of unseen future things as already certain (Hebrews 11:1). That is not a human invention. It is the human moral correspondent to God’s own mode of operating: the God who “calls things that are not as though they were” (Romans 4:17) commands us to do the same — to treat what is not yet seen as already substantial, what is not yet possessed as already real, what is not yet fulfilled as already certain.

This is not a peripheral command. Hebrews 11:6 states it as the non-negotiable condition of pleasing God at all: “without faith it is impossible to be well pleasing to Him.” And Romans 4:17-18 makes the correspondence explicit — God calls non-existent things as existent; Abraham “in hope believed against hope.” Same certainty, different mode.

Hebrews 12 drives the point home. In verse 22, the writer declares, ‘you have come to Mount Zion’ — arrival spoken as already accomplished. Yet verse 25 immediately warns against refusing the One who speaks from heaven — ‘how much more will we not escape who turn away from him who warns from heaven’ — treating the outcome as something that can still be forfeited. This is not a contradiction. It is the ‘already/not yet’ of a God who sees the destination as fixed while the traveler is still on the road. Open Theism cannot account for this. A God who does not know whether His people will persevere has no business announcing their arrival before they get there.

What is declared, proclaimed, confessed, exemplified, and — in the case of Isaiah 41 — commanded to believe as proof of true divinity is the opposite: that God foreknows the end from the beginning, that His knowledge is without limit, and that the ability to declare the future is the very thing that sets the living God apart from every idol.

Conclusion: Consistency Is Not Optional

The Biblical Unitarian critique of Trinitarianism is grounded in a simple, irreducible principle: the Scripture must be allowed to say what it says. A doctrine that can only be sustained by reinterpreting explicit declarations through a philosophical lens is not a biblical doctrine. It is a tradition, however ancient, dressed in biblical clothing.

That principle does not belong to the critique of Trinitarianism alone. It belongs to every doctrine. Including Open Theism.

Ezekiel 18 does not teach divine ignorance. It teaches divine consistency of character. God responds to the repentant and the unrepentant according to who He is — not because He did not know what they would do, but because His holy nature is applied with unwavering equity to every moral situation. This is not improvisation. It is faithfulness.

The passages Open Theism cites are real. They deserve engagement, not dismissal. But they are fully explained by the biblical categories of anthropomorphism, divine condescension, covenantal confirmation, and most importantly, God’s own stated reason: His consistent moral character, which responds to repentance and rebellion with unwavering equity regardless of what He already knows. Ezekiel 18 is not God confessing uncertainty — it is God defending His justice. His responsiveness is not the product of ignorance. It is the expression of who He is.

And this truth is strongly enforced by texts that cannot be so explained by Open Theism: a pagan king named 150 years before his birth, a reformer named 300 years before his birth, and a plan of redemption described as formed before the foundation of the world.

Biblical Unitarians are called to a higher standard than merely avoiding one error. They are called to let the whole counsel of Scripture speak. That counsel declares God’s foreknowledge clearly, repeatedly, and without apology.

The mirror error must be recognized for what it is: importing philosophy into the text, silencing declarations with inferences, and defending a doctrine that Scripture never names, never proclaims, never commands — while condemning others for doing exactly that.

In their zeal, Trinitarians have wrestled with texts they believe create a tension, and conceal a deeper truth which they believe to be answered by a man-made doctrine called the Trinity. Likewise, some Biblical Unitarians have wrestled with texts they believe create tension and conceal a deeper truth, which they believe is answered by a man-made doctrine called “Open Theism.”

But in the final analysis, both man-made doctrines are mirror images of each other. They both follow the same basic paradigm: create a false dilemma, jump to conclusions, and produce a doctrine not named, proclaimed, confessed, explained or commanded in scripture that negates a doctrine that meets every one of those criteria.

For Trinitarians, the doctrine they reject is technically called “Biblical Unitarianism” but biblically is called “God is one He” and Jesus is the Anointed One, the Son of the living God.

For Open Theists, the doctrine they reject is biblically called “foreknowledge,” and it is named, proclaimed, confessed, explained and even commanded in scripture.

If Biblical Unitarians reject Trinitarianism but embrace Open Theism, they really need to take a hard look at the basis of each decision. On what grounds do they accept one and reject the other, when the structural methodology of both is virtually identical — differing only in which category of theology the eisegesis is applied to. The two doctrines share the same spiritual DNA.

“Do you think this, O man who judges those who practice such things, and do the same, that you will escape the judgment of God?” (Romans 2:3)