John 17:3

Reading

"The only true God" distinguishes the Father from false gods and idols, not from the Son or Spirit. The Son is included within the identity of the "true God" as a distinct person sharing the same divine nature. 1 John 5:20 explicitly applies the title "the true God" to Jesus Christ, confirming that "only" here is not exclusionary of the Son.

Reasoning

In Trinitarian theology, the Father, Son, and Spirit are not three Gods but one God in three persons. When Jesus calls the Father "the only true God," he is affirming the Father's unique role as the source of divinity — the unbegotten origin from whom the Son's divine nature proceeds. This is not a denial of the Son's deity but an affirmation of the Father's particular role within the Godhead. Compare: a son can say "my father is the head of this family" without denying that he himself is a member of the family. The distinction is one of origin and role, not of nature. John's Gospel elsewhere attributes divine prerogatives to Jesus — creating all things (1:3), giving life (5:21), receiving worship (9:38), and being explicitly called theos (1:1). Thomas calls Jesus "My Lord and my God" (20:28) with Jesus's apparent approval. The "sending" language reflects the eternal relationship of origin (the Father sends, the Son is sent) without implying inferiority of nature — just as a king who sends an ambassador with full royal authority is distinguished from the ambassador in role, not in the authority they bear.

Strongest counterargument

The word monon (only) is inherently exclusive. Jesus himself, in direct prayer to the Father, identifies someone other than himself as "the only true God." He then describes himself in a different category entirely: the one who was sent. The sender and the sent are distinguished, and only the sender is called "the only true God."

Key scholars: D.A. Carson, Andreas Köstenberger, Murray Harris

Reading

This is an explicit, unambiguous identification: someone other than Jesus is "the only true God." The word monon is exclusive by definition. Jesus places himself in a separate category — the sent one, the agent, the Christ — while the Father alone occupies the category of "the only true God." This verse, spoken by Jesus in prayer, is extraordinarily difficult for Trinitarianism.

Reasoning

The structure of the verse creates a clear distinction: eternal life consists in knowing (1) the Father as the only true God, and (2) Jesus Christ as the one sent by that God. These are two different identifications. The sending language (apesteilas) is agency language — the sent one acts on behalf of the sender but is not the sender. This aligns with the Jewish shaliach principle and with Jesus's repeated self-identification as the Father's agent throughout John. Dustin Smith argues that this verse is definitive for understanding Jesus's own theology: Jesus identifies "the only true God" as "you, Father" — using the second person, addressing someone other than himself — and then identifies himself separately as "Jesus Christ whom you have sent." The Father alone is the only true God, and Jesus is his sent agent. This is not an ambiguous passage; it is Jesus's own statement of how things stand (see Smith, Wisdom Christology in the Gospel of John, Wipf & Stock, 2024; BiblicalUnitarian.com). Dale Tuggy presses the logic: if Jesus IS the only true God, then this verse has Jesus excluding himself from the category he himself occupies. Trinitarians must either say Jesus misspoke, or that "only true God" means something other than what it plainly says. Neither option is satisfactory (see Tuggy, What is the Trinity?, 2017). This distinction between God and Jesus is not a weakness in John's theology — it is its strength. Eternal life is defined here as knowing two distinct realities: the one true God, and the human Messiah he sent. Jesus's identity as God's sent agent — a genuine human being who lived in complete trust and obedience to his God — is what gives the promise of eternal life its force. His resurrection was the Father's vindication of a faithful human life. If Jesus were himself God, the entire logic of the prayer collapses: a divine being does not need to entrust himself to God, cannot genuinely die, and offers no model for human faithfulness. The clear distinction in this verse is what makes the Christian hope tangible.

Strongest counterargument

1 John 5:20 may apply the title "the true God" to Jesus Christ. However, the grammatical antecedent of "this one" (houtos) in 1 John 5:20 is ambiguous — many scholars, including Trinitarian scholar I. Howard Marshall, acknowledge it likely refers to the Father rather than to Jesus.

Key scholars: Anthony Buzzard, Friedrich Schleiermacher (historically), Michael Servetus (historically)

Reading

John's Gospel deliberately holds both claims in tension: the Father is "the only true God" (17:3) AND the Word "was God" (1:1). This is not contradiction but dialectic — a Christology in development that had not yet resolved into the formal categories of later Trinitarian doctrine. The tension is the theology.

Reasoning

The Fourth Gospel contains both the highest Christological claims in the NT (the Prologue, "I and the Father are one," Thomas's confession) and the clearest subordinationist statements ("the Father is greater than I," "my God and your God," this verse). Rather than harmonising these by privileging one set over the other, this approach takes both seriously as reflecting the community's experience of Jesus — one they could not yet systematise.

Strongest counterargument

Describing the tension as "deliberate" or "dialectic" may avoid rather than answer the question. Both Trinitarians and Unitarians offer actual answers; this position risks being a sophisticated form of agnosticism that sounds scholarly while saying "we don't know."

Key scholars: Raymond Brown, Rudolf Schnackenburg