Now here’s an exciting title (sarcasm intended), but bear with me. The topics of Monotheism and Modalism represent a key juncture in understanding why unitarians reject the Trinity and how Trinitarians actually understand God’s nature. After 50 years as a Christadelphian, I can tell you exactly how this argument works – because I used it myself.
This post is part of my Trinity series. For full context and recommended reading order, start with the series introduction.
The Unitarian Logical Objection
When I was a unitarian, I didn’t primarily appeal to the Shema as a slogan to defeat Trinitarian doctrine, though Deuteronomy 6:4 certainly mattered. The more compelling argument was logical: Trinity creates absurdities that prove it can’t be true.
Here’s how the argument goes:
- If Father, Son, and Spirit are all God, then when Jesus prays to the Father, that’s God praying to God. How does that make sense? Is God having a conversation with himself? That’s not prayer – that’s schizophrenia.
- When Revelation says God gave the revelation to Jesus, that’s God giving something to God. How can God give something to someone who already is God? How can God not know something that God knows? The logic falls apart.
- When Jesus says “the Father is greater than I” (John 14:28), that’s God saying God is greater than God. Contradiction.
- When Jesus is tempted, that’s God being tempted – but James 1:13 says God cannot be tempted. Another contradiction.
The unitarian conclusion: Trinity must be incoherent because it creates these logical impossibilities. The only way Trinitarians could maintain their position is if they secretly believe Father, Son, and Spirit are just different masks or modes of the same person – God playing different roles at different times. And if that’s what they believe, it’s obviously false because you can’t pray to yourself or give yourself a revelation.
The Strawman I Didn’t Realise I Was Building
Here’s what I didn’t understand for 50 years: I was arguing against modalism, not the Trinity.
Trinitarians don’t believe Father, Son, and Spirit are different modes or masks of one person. They explicitly reject that view – it’s called modalism, and the early church condemned it as heresy centuries ago.
But as a unitarian, I couldn’t conceive of any other way Trinity could work. Three persons, one God? That sounded like word games. Three modes of one person was the only framework that made sense to me, so I assumed that’s what Trinitarians must secretly believe, even if they denied it.
This inability to conceive of Trinity except as modalism or polytheism reflects something deeper I’ve explored in my article on the rationalist captivity of Christian faith. When we demand that all theological truth conform perfectly to human logical categories – when we insist that if we can’t fully explain something, it must be false – we’ve elevated reason above revelation. The unitarian argument against Trinity often isn’t primarily exegetical; it’s rationalist at its core. ‘This doesn’t fit my logical framework, therefore it can’t be true.’ But mystery isn’t intellectual failure or lazy thinking. It’s recognition that finite minds encounter limits when approaching infinite reality. The Renaissance legacy of rationalism taught us to reject what we cannot fully comprehend, but Scripture calls us to embrace revealed truth even when it transcends our categories.
This is the fundamental disconnect. Unitarians argue: “If you say Father, Son, and Spirit are all God, you must mean they’re the same person in different modes, and here’s why that doesn’t work.” Trinitarians respond: “We don’t believe that. We explicitly reject modalism. You’re arguing against a position we don’t hold.”
It’s like spending years arguing against a Catholic doctrine of salvation by works alone, only to discover Catholics actually teach salvation by grace through faith working in love. You’ve been fighting a strawman.
What Trinitarians Actually Believe
The doctrine of the Trinity states that there is one God who exists eternally in three distinct persons: the Father, the Son, and the Holy Spirit. These three persons are not modes, masks, or roles – they are distinct centers of consciousness, will, and action who share one divine essence.
- One God – There is only one divine being, one divine essence, one Godhead. Trinitarians are monotheists. We don’t believe in three gods.
- Three persons – Within that one divine being exist three distinct persons who are eternally related to one another. The Father is not the Son. The Son is not the Spirit. The Spirit is not the Father. They are genuinely distinct.
- Fully divine – Each person possesses the complete divine nature. The Father is fully God. The Son is fully God. The Spirit is fully God. Not three parts of God, but three persons who each possess the whole of divinity.
This isn’t modalism. Modalism teaches that God is one person who appears in different modes at different times – sometimes as Father, sometimes as Son, sometimes as Spirit, like an actor playing different roles. The early church rejected this because Scripture clearly shows Father, Son, and Spirit existing simultaneously and relating to one another.
How This Solves the “Logical Problems”
Once you understand that Father, Son, and Spirit are distinct persons rather than modes, the supposed logical contradictions disappear:
- When Jesus prays to the Father, that’s not God praying to God in some self-referential loop. It’s the Son (who is God) communing with the Father (who is God). Two distinct divine persons in relationship.
- When God gives the revelation to Jesus, that’s the Father (who is God) giving revelation to the Son (who is God). The Father and Son possess the same divine essence but are distinct persons with distinct roles in the economy of salvation.
- When Jesus says “the Father is greater than I,” he’s speaking about the relationship between persons and their respective roles in salvation history. The Father sent; the Son was sent. The Father is the source; the Son proceeds from the Father. This speaks to order and relationship, not to inequality of nature or essence.
- When Jesus is tempted through his human nature, this doesn’t contradict God’s inability to be tempted. Jesus experiences temptation as the God-man through his complete humanity, while his divine nature remains untouchable by evil. This is only a contradiction if you collapse the distinction between persons and natures.
The logical problems only exist if you assume modalism. Once you understand distinct personhood, the objections lose their force.
But Doesn’t This Violate Monotheism?
This is where Deuteronomy 6:4 becomes relevant:
“Hear, O Israel: The LORD our God, the LORD is one.”
After 50 years subsumed in this declaration, I understand why Trinity feels like polytheism. The Shema is the bedrock of Jewish monotheism, the declaration that sets Israel apart from pagan nations with their pantheons of gods. How can Christians claim to be monotheists while worshiping Father, Son, and Spirit?
The answer lies in understanding what “one” means in this context. The Hebrew word echad can indicate compound unity – one made up of multiple parts working in perfect harmony. (The same word is used in Genesis 2:24: “the two shall become one flesh.”)
The Trinity doesn’t violate monotheism because we’re not worshiping three separate gods. We’re worshiping one God who exists in eternal relationship within himself – three persons sharing one divine essence, one divine will, one divine power.
Pagan polytheism has multiple separate beings, each with their own agenda, competing for power and worship. That’s not the Trinity. Father, Son, and Spirit share one divine nature, work in perfect unity, and accomplish one divine purpose.
The Shema affirms that there is one God, one divine being, one source of all that exists. The Trinity affirms this while recognising that within God’s unity exists genuine personal distinction. It’s mystery, certainly – but it’s not polytheism.
The Roles of the Trinity in Salvation
The distinct personhood of Father, Son, and Spirit becomes especially clear when we look at salvation. If modalism were true – if these were just different roles of one person – then salvation wouldn’t work the way Scripture describes it.
- The Father is the initiator of salvation. He sent Jesus Christ to die for our sins (John 3:16). He justifies us through faith in Jesus (Romans 8:33). The Father will glorify us at the end of time (1 Thessalonians 5:9).
- The Son saves us from our sins, dying on the cross for us (1 Peter 3:18). He intercedes for us before the Father (Romans 8:34). Jesus is the righteous judge of the living and the dead (Matthew 25:31-46).
- The Holy Spirit convicts us of our sin (John 16:8). The Spirit regenerates us and gives us new life (Titus 3:5). The Holy Spirit indwells us and empowers us to live our new lives in Christ (Romans 8:9-11).
We are baptised in the name of the Father, the Son, and the Holy Spirit (Matthew 28:19-20). We receive the grace of Jesus, the love of the Father, and the fellowship of the Holy Spirit (2 Corinthians 13:14).
These are not different roles of one person at different times. They are three distinct persons working in perfect harmony to accomplish our salvation. The Father sends, the Son is sent, and the Spirit applies the finished work of Christ to our lives. Each plays a unique role that cannot be collapsed into the others.
Modalism Is Not Trinitarian Doctrine
This is the crucial point: Trinitarians explicitly reject modalism. We don’t believe God is one person wearing different masks. We believe God is three distinct persons sharing one divine essence.
Modalism was condemned as heresy in the early centuries of Christianity precisely because it contradicts Scripture’s portrayal of Father, Son, and Spirit existing simultaneously and relating to one another. At Jesus’ baptism, the Son is baptised, the Spirit descends like a dove, and the Father speaks from heaven. That’s not one person in different modes – that’s three persons present at once.
When unitarians argue that Trinity must be modalism and then show why modalism doesn’t work, they’re fighting a doctrine that Trinitarians don’t hold. It’s a powerful rhetorical move, but it’s ultimately attacking a strawman.
The Challenge for Former Unitarians
I understand the difficulty here. For 50 years, I couldn’t conceive of how “three persons, one God” could work without being either polytheism or modalism. It felt like Trinitarians were playing word games, trying to have it both ways.
What helped me was recognising that my inability to fully comprehend God’s nature doesn’t make it false. We’re finite creatures trying to understand infinite reality. That we can’t fully grasp how three persons share one divine essence doesn’t mean it’s incoherent – it means it’s mystery.
Scripture clearly teaches:
- There is one God (monotheism)
- The Father is God
- The Son is God
- The Spirit is God
- Father, Son, and Spirit are distinct (not modes)
The Trinity is the church’s attempt to hold all these biblical truths together without reducing any of them. It’s not perfect language – no human words can fully capture divine reality – but it’s faithful to what Scripture reveals.
Conclusion
Monotheism and modalism represent the twin dangers we must avoid. Modalism preserves God’s unity by denying real distinction between Father, Son, and Spirit. Tritheism preserves distinction by denying genuine unity.
The Trinity walks the biblical path between these errors: one God in three persons, unity and distinction held together, mystery and revelation in perfect balance.
This isn’t logical gymnastics or theological word games. It’s the church’s faithful attempt to articulate what Scripture reveals about God’s nature – that the one true God exists eternally in loving relationship within himself, Father, Son, and Spirit, united in essence and distinct in person.
That’s the God who saves us. Not a solitary monad but a divine community of love, inviting us into relationship with the triune God revealed in Scripture.