1 The Text
Greek (NA28)
…ἐν τῷ υἱῷ αὐτοῦ Ἰησοῦ Χριστῷ. οὗτός ἐστιν ὁ ἀληθινὸς θεὸς καὶ ζωὴ αἰώνιος (1 John 5:20, end of verse).
Key clause highlighted: houtos estin ho alēthinios theos (this is the true God)
NIV
We know also that the Son of God has come and has given us understanding, so that we may know him who is true. And we are in him who is true by being in his Son Jesus Christ. He is the true God and eternal life.
ESV
And we know that the Son of God has come and has given us understanding, so that we may know him who is true; and we are in him who is true, in his Son Jesus Christ. He is the true God and eternal life.
NRSVue
And we know that the Son of God has come and has given us understanding so that we may know him who is true; and we are in the true one, in his Son Jesus Christ. This is the true God and eternal life.
NASBRE
And we know that the Son of God has come, and has given us understanding so that we may know Him who is true; and we are in Him who is true, in His Son Jesus Christ. This is the true God and eternal life.
REV
And we know that the Son of God has come, and has given us an understanding, so that we know him who is true. And we are in him who is true, in his Son Jesus Christ. This is the true God, and eternal life.
2 Context
First John is written in familial, covenant language: knowing God, abiding in him, confessing the Son, testing the spirits. Chapter 5 closes with a dense sequence about testimony, life, and confidence before God. Verse 20 is the letter's last major theological statement before the brief closing (5:21).
The exegetical battle centres on the demonstrative houtos ("this one" / "this"): does it point to the nearest grammatically agreeable antecedent (often taken as Jesus Christ), or to the remoter "him who is true" / God, consistent with how John uses "true God" elsewhere?
Trinitarians often read the verse as John's climactic identification of Jesus as theos. Biblical Unitarians reply that Johannine usage, parallels in Acts, and the immediate repetition of "the true one" (ho alēthinios) favour taking "the true God" as the Father — which also harmonises with Jesus's own definition of eternal life in John 17:3.
3 The Debate
Trinitarian
Reading
The natural antecedent of houtos is Jesus Christ, named immediately before ("in his Son Jesus Christ. This one is the true God"). John would then be calling Jesus the true God explicitly — a fitting climax to the Gospel and Epistles.
Reasoning
Proponents argue that John is capable of startling Christological affirmations and that reading houtos as Jesus best explains the flow from incarnation ("the Son of God has come") to knowledge of God. Some commentators hold that the entire complex "Jesus Christ" is the subject of the confession.
Strongest counterargument
Demonstratives in Greek follow context, not only proximity. Acts 7:18–19 shows houtos picking up a remoter referent. 2 John 7 parallels 1 John 5:20's structure; if "this" must always attach to the nearest noun, absurd readings follow in 2 John. Many Trinitarian commentators (e.g. I. Howard Marshall on 1 John) have argued the Father is the referent.
Key scholars: I. Howard Marshall, John Stott, Karen Jobes
Biblical Unitarian
Reading
"The true God" refers to the Father — the one called "the true one" twice in the same verse. Jesus is the Son in whom believers abide; the God who is known through the Son remains the Father. This preserves the same pattern as John 17:3: the Father is the only true God, and Jesus is the one he sent.
Reasoning
Elsewhere in Scripture, "true God" language for the God of Israel points to the Father (Jer 10:10; John 17:3; 1 Thess 1:9). John is unlikely to use the same phrase with a completely different referent without signalling it. The REV's punctuation ("This is the true God, and eternal life") reflects a Father-referent reading. For detailed argumentation on houtos and parallels, see BiblicalUnitarian.com (1 John 5:20).
Strongest counterargument
If the Father alone is meant, some readers find the placement of houtos after "Jesus Christ" rhetorically odd. Defenders reply that Greek routinely resumes a main topic after a prepositional phrase — especially when the verse began with the Son's coming and returns to the one ultimate object of Christian knowledge.
Key scholars: Anthony Buzzard, Dale Tuggy, John Biddle (historically)
Scholarly Context
Reading
Commentators split. Some Trinitarian scholars take the Father as the referent to avoid tension with John 17:3; others take the Son. The debate is widely acknowledged as finely balanced on grammar alone.
Reasoning
Lexical studies of houtos show that proximity is a default, not a rule. The immediate context twice calls the Father "the true one" (ton alēthinon / tō alēthinō), which supports taking the climactic "true God" as the same figure. But the Son's proximity keeps the dispute alive in the secondary literature.
Strongest counterargument
If John intended deliberate ambiguity, both confessional traditions may be over-reading a sentence that originally functioned primarily as covenantal exhortation rather than metaphysical precision.
Key scholars: Raymond Brown, Judith Lieu, John Painter
Modalism (Oneness)
Reading
The Son and Father share one divine identity; identifying Jesus as "the true God" would express that unity rather than two beings.
Reasoning
Oneness readings often combine 5:20 with Johannine "I and the Father are one" language.
Strongest counterargument
The verse still distinguishes "his Son Jesus Christ" from the one called true God in many grammatical analyses; readers must decide whether that distinction is personal or merely economic.
Key scholars: David K. Bernard, David Norris
? Questions to Ask This Text
Who is "him who is true" earlier in the verse — the Father, or the Son?
Does houtos more naturally resume "Jesus Christ" or "him who is true"?
How does this verse relate to John 17:3? Can the same author use "true God" in two incompatible senses?
What pattern do you see in 1 John: is the Father usually the primary referent of "God"?
Key Concepts for This Passage
Understanding these concepts will help you evaluate the arguments above:
4 Related Passages
5 Go Deeper
Trinitarian perspective
John Stott, The Letters of John (IVP, 1988). Karen Jobes, 1, 2, & 3 John (ECNT, 2014).
Biblical Unitarian perspective
BiblicalUnitarian.com — 1 John 5:20. Dale Tuggy, What is the Trinity? (2017).
Scholarly Context
I. Howard Marshall, The Epistles of John (NICNT, 1978). Raymond E. Brown, The Epistles of John (Anchor Bible, 1982).
Grammar and referent
Biblical Hermeneutics Stack Exchange (discussion of houtos).