# John 17.21

<!-- type: passage | created: 2026-07-12 | updated: 2026-07-03 -->


**Book:** [John](/codex/john-the-apostle/) · ASV / WEB / KJV / YLT

## Verse

**ASV:**
> 21. <span class="rl-speech">that they may all be one; even as thou, Father, art in me, and I in thee, that they also may be in us: that the world may believe that thou didst send me.</span> (John 17:21, ASV)

**WEB:**
> 21. <span class="rl-speech">that they may all be one; even as you, Father, are in me, and I in you, that they also may be one in us; that the world may believe that you sent me.</span> (John 17:21, WEB)

**KJV:**
> 21. <span class="rl-speech">That they all may be one; as thou, Father, art in me, and I in thee, that they also may be one in us: that the world may believe that thou hast sent me.</span> (John 17:21, KJV)

**YLT:**
> 21. <span class="rl-speech">that they all may be one, as Thou Father [art] in me, and I in Thee; that they also in us may be one, that the world may believe that Thou didst send me.</span> (John 17:21, YLT)

## Immediate context (±2 verses)

**ASV:**
> 19. <span class="rl-speech">And for their sakes I sanctify myself, that they themselves also may be sanctified in truth.</span> 20. <span class="rl-speech">Neither for these only do I pray, but for them also that believe on me through their word;</span> 21. <span class="rl-speech">that they may all be one; even as thou, Father, art in me, and I in thee, that they also may be in us: that the world may believe that thou didst send me.</span> 22. <span class="rl-speech">And the glory which thou hast given me I have given unto them; that they may be one, even as we are one;</span> 23. <span class="rl-speech">I in them, and thou in me, that they may be perfected into one; that the world may know that thou didst send me, and lovedst them, even as thou lovedst me.</span> (John 17:19-23, ASV)

**WEB:**
> 19. <span class="rl-speech">For their sakes I sanctify myself, that they themselves also may be sanctified in truth.</span> 20. <span class="rl-speech">Not for these only do I pray, but for those also who believe in me through their word,</span> 21. <span class="rl-speech">that they may all be one; even as you, Father, are in me, and I in you, that they also may be one in us; that the world may believe that you sent me.</span> 22. <span class="rl-speech">The glory which you have given me, I have given to them; that they may be one, even as we are one;</span> 23. <span class="rl-speech">I in them, and you in me, that they may be perfected into one; that the world may know that you sent me, and loved them, even as you loved me.</span> (John 17:19-23, WEB)

**KJV:**
> 19. <span class="rl-speech">And for their sakes I sanctify myself, that they also might be sanctified through the truth.</span> 20. <span class="rl-speech">Neither pray I for these alone, but for them also which shall believe on me through their word;</span> 21. <span class="rl-speech">That they all may be one; as thou, Father, art in me, and I in thee, that they also may be one in us: that the world may believe that thou hast sent me.</span> 22. <span class="rl-speech">And the glory which thou gavest me I have given them; that they may be one, even as we are one:</span> 23. <span class="rl-speech">I in them, and thou in me, that they may be made perfect in one; and that the world may know that thou hast sent me, and hast loved them, as thou hast loved me.</span> (John 17:19-23, KJV)

**YLT:**
> 19. <span class="rl-speech">and for them do I sanctify myself, that they also themselves may be sanctified in truth.</span> 20. <span class="rl-speech">'And not in regard to these alone do I ask, but also in regard to those who shall be believing, through their word, in me;</span> 21. <span class="rl-speech">that they all may be one, as Thou Father [art] in me, and I in Thee; that they also in us may be one, that the world may believe that Thou didst send me.</span> 22. <span class="rl-speech">'And I, the glory that thou hast given to me, have given to them, that they may be one as we are one;</span> 23. <span class="rl-speech">I in them, and Thou in me, that they may be perfected into one, and that the world may know that Thou didst send me, and didst love them as Thou didst love me.</span> (John 17:19-23, YLT)

## Setting

- **Speaker:** Jesus (in the high-priestly prayer to the Father, the longest recorded prayer of Jesus in Scripture; John 17:1-26)
- **Audience:** the Father (the direct addressee of the prayer) + the eleven disciples (implicit overhearing audience; v. 13, *"these things I speak in the world, that they might have my joy fulfilled in themselves"*) + the future church (vv. 20-26 are explicitly *for those who would believe through the apostles' word*, including all subsequent Christian generations) + the reader of John's Gospel
- **Location:** Jerusalem, on the way from the Upper Room to Gethsemane (after the Last Supper of John 13-16; before the Garden of Gethsemane of John 18:1), or possibly the Upper Room itself extended
- **Time period:** events Thursday evening of Passion Week, c. AD 30/33 (Nisan 14 by Johannine reckoning); composed c. AD 85-95 by John the Apostle (Ephesus)
- **Narrative context:** the *high-priestly prayer* (John 17), Jesus's final extended prayer before His arrest, trial, and crucifixion. The prayer has three movements: vv. 1-5 (Jesus prays for Himself, for His glorification through the cross); vv. 6-19 (Jesus prays for the eleven apostles, for their protection, sanctification, and mission); vv. 20-26 (Jesus prays for the future church, for unity, indwelling glory, and final reunion with Himself). Verse 21 is the central petition of the third movement: that the future church's unity may *reflect* the intra-Trinitarian unity of Father and Son and thereby become the *evidentiary basis* for the world's belief in Jesus's divine mission.

## Theological reading

John 17:21 is the **single highest-stakes prayer for the church in all of Scripture**, Jesus's own prayer that the unity of His disciples might mirror the unity of the Father and the Son, and that this church-unity might be the *evangelistic-evidential ground* by which the world comes to believe in Him. The verse generates three distinct theological loci: **Trinitarian doctrine** (the intra-Trinitarian unity that the church-unity reflects), **ecclesiology** (the nature and ground of Christian unity), and **missiology** (the evidential function of church-unity for the world's belief).

### The intra-Trinitarian foundation, *perichoresis*

The prayer's analogy is *kathōs*, "as / according as." The unity Jesus prays for the church is structurally analogous to the unity Father-Son already possess. The Father-Son unity is described by the mutual-indwelling formula: *"thou, Father, art in me, and I in thee."*

This is the patristic-medieval doctrine of *perichoresis* (Greek περιχώρησις), the mutual indwelling and interpenetration of the divine persons. Each person of the Trinity fully indwells each other person, sharing the one divine essence while remaining personally distinct.

The patristic locus classicus for *perichoresis* is **John of Damascus** (*Exposition of the Orthodox Faith* I.8, 8th c.) building on the prior Cappadocian-Eastern tradition. The Western Latin equivalent (*circumincessio*) is developed in the medieval scholastic tradition (Aquinas, *Summa* I.42.5). The doctrine became central to 20th-century revivals of Trinitarian theology (Karl Barth, Catherine LaCugna, Jürgen Moltmann, John Zizioulas) where Father-Son-Spirit *perichoresis* is treated as the foundational divine reality from which all creaturely communion derives.

### The ecclesiological derivative

What Jesus prays for the church is not *replication* of the Father-Son unity (the church does not become a fourth divine person) but *analogical participation* in it. The unity Jesus prays for is:

- **Real** (not merely organizational or symbolic), "they also may be in us" indicates ontological participation in the divine communion
- **Visible** (because otherwise it cannot function as the world's evidential ground)
- **Trinity-shaped** (mutual indwelling, mutual love, mutual self-giving)
- **Spirit-mediated** (the Spirit poured out at Pentecost is the agent of this unity-in-Christ, see John 16:13-15; 1 Cor 12:12-13)

The visible-unity demand creates **the ecumenical question**: should the historic divisions of the church (East-West Schism 1054; the Reformation; the various Protestant divisions) be understood as failures to live out John 17:21? The 20th-century ecumenical movement was substantially motivated by this verse. The conservative Protestant response: yes, division is failure, but the unity Jesus prays for is *spiritual / mystical* unity in Christ which exists across the visible-organizational divisions among genuine believers, not the bureaucratic-institutional unity the ecumenical movement sometimes pursues. The Catholic / Orthodox response: the visible unity of the Body of Christ requires sacramental and doctrinal-confessional unity, which historic divisions break.

### The missional / evangelistic stakes

The prayer's *purpose clause* is striking: *"that the world may believe that thou didst send me."*

Jesus stakes the *evangelistic credibility* of His own divine mission on the *visible unity* of His church. The world's belief in Jesus as God-sent is positively correlated with the church's visible unity-in-love. The contrapositive is sobering: when the visible church is fractured by hatred, schism, and division, the world's belief in Jesus's divine mission is correspondingly impeded.

This is one of the **strongest arguments against church-internal political weaponization, character assassination, and tribal warfare**. The biblical warrant for being decent to other Christians is not pragmatic-PR but Christological-evangelistic: the world believes Jesus is divine on the evidential basis of how Christians treat one another. Every public Christian battle is a witness, to the truth of Christ's divine mission (when love is preserved) or against it (when hatred displays).

### Patristic reading

**Augustine** (*Tractates on the Gospel of John* 110, c. AD 416) emphasizes the *love* dimension: the unity of the Father and the Son is *the love which is the Holy Spirit*; the unity Jesus prays for the church is *the same Spirit's outpouring* on the body. The Trinitarian unity is not abstract metaphysics but love-in-communion; the church's unity is participation in that same love.

**Cyril of Alexandria** (*Commentary on John* 11, 5th c.) reads the verse Christologically against the contemporary Christological controversies: the Person who prays this prayer is the one Person of Christ in two natures; the unity He prays for participates in the *hypostatic union*'s love-bond and extends it to the church.

### Reformed reading

**John Calvin** (*Commentary on John* ad loc.) emphasizes the *invisible / mystical* dimension: the unity Jesus prays for is fundamentally union-with-Christ in faith and the Spirit, which produces visible unity in genuine love but which is not identical to bureaucratic-institutional unity. The Westminster Confession Larger Catechism Q. 168 cites John 17:21 for the church's "communion in grace and glory", a unity that is real but spiritual, finding visible expression in love and visible-church-membership without requiring centralized institutional unity.

### Apologetic deployment

The verse functions in two apologetic directions:

1. **As evangelistic-credibility ground (positive deployment).** When Christians love one another visibly and sacrificially, the world has evidential grounds to take Jesus's divine-mission claim seriously. The early-church history (Acts 2:44-47; Tertullian's *"See how they love one another"* observation about the second-century church) shows this principle empirically: visible Christian love drew converts.

2. **As internal-rebuke ground (negative deployment).** When the church is publicly divided by hatred, character assassination, or schism, the world is *epistemically blocked* from believing, and the church itself bears the responsibility per Jesus's own prayer. This is a serious rebuke for contemporary American evangelical political-tribal warfare, denominational hostility, and online theological invective. The [Hypocrisy](/codex/hypocrisy/) defeater concedes this point honestly.

The verse is also the **Trinitarian-deity-of-Christ proof-text** in a subtle register: Jesus assumes He and the Father share a unity of indwelling and life that the human church *participates in by analogy*. This presupposes a real divine-personal communion between the Son and the Father, exactly the Trinitarian framework (or, in the Oneness Pentecostal reading, the one-God-in-Son-manifestation framework where the Son-manifestation perfectly indwells the Father-source). See [Trinity vs Oneness vs Modalism vs Arianism](/codex/trinity-vs-oneness-vs-modalism-vs-arianism/) for the multi-position comparison.

### The Oneness Pentecostal reading

In ris3n's Oneness Pentecostal framework, John 17:21 is read as the one God's *prayer in His Son-manifestation* expressing the perfect Son-Father unity (which is the one God's self-unity expressed through the incarnational distinction). The church's unity-with-the-divine is participation in this one-God-in-Christ reality. The Oneness reading preserves the prayer's force without requiring the Trinitarian Father-Son-as-distinct-persons reading. See [Trinity vs Oneness vs Modalism vs Arianism](/codex/trinity-vs-oneness-vs-modalism-vs-arianism/) for the multi-position dispute.

### Canonical-theological connections

- **John 10:30**, *"I and my Father are one"*, the prior intra-Trinitarian unity claim that this prayer assumes
- **John 14:10-11**, *"I am in the Father, and the Father in me"*, the perichoretic indwelling
- **John 14:20**, *"At that day ye shall know that I am in my Father, and ye in me, and I in you"*, the explicit church-participation in the Trinitarian indwelling (the Pentecost-inauguration)
- **John 15:1-8**, vine and branches; abiding-in-Christ-and-bearing-fruit
- **Ephesians 4:1-6**, the seven-fold one (one body, one Spirit, one hope, one Lord, one faith, one baptism, one God and Father), Paul's ecclesiological application
- **1 Corinthians 12:12-27**, the body-with-many-members; the Spirit's gift of unity
- **Acts 2:42-47; 4:32-37**, the early church's visible-unity-in-love as the original embodiment of Jesus's prayer
- **Colossians 3:11-14**, the put-off-the-old-put-on-the-new ecclesiology grounded in unity

## Key words

- [G3962 - pater](/codex/g3962-pater/), *patēr*, "Father (Strong's G3962)
- [G1520 - heis](/codex/g1520-heis/), *heis*, "one" (Strong's G1520), the central unity-vocabulary
- [G2889 - kosmos](/codex/g2889-kosmos/), *kosmos*, "world" (Strong's G2889), the audience of the missional witness
- [G3956 - pas](/codex/g3956-pas/), *pas*, "all" (Strong's G3956), the universal scope of the church-unity prayed for
- [G4100 - pisteuo](/codex/g4100-pisteuo/), *pisteuō*, "believe" (Strong's G4100), the *world's* response on the evidential ground of the church's visible unity

## See also

### Direct doctrinal hubs
- [Trinity](/codex/trinity/), the doctrinal frame for the intra-Trinitarian unity reflected in the prayer
- [Trinity vs Oneness vs Modalism vs Arianism](/codex/trinity-vs-oneness-vs-modalism-vs-arianism/), multi-position dispute
- [Christology](/codex/christianity/), broader Christological frame
- [Christs Deity](/codex/christs-deity/), the divine-self-witnessing presupposed
- [Hypostatic Union](/codex/hypostatic-union/), the Christological structure of the praying Person
- [Logos Christology](/codex/logos-christology/), Johannine framework
- [Soteriology (Salvation)](/codex/soteriology-salvation/), adjacent doctrinal frame
- [Sanctification](/codex/sanctification/), vv. 17-19 sanctification context
- [Evangelism](/codex/evangelism/), the missional implication

### Companion John passages
- *John 10:30*, I and the Father are one
- *John 14:10-11, 20*, the perichoretic indwelling extended to disciples
- *John 15:1-8*, vine and branches (rich hub at [John 14.6](/codex/john-14-6/) adjacent)
- *John 17:1-26*, the full high-priestly prayer (rich-hub-promotion candidate for whole-chapter rich hub)

### Ecclesiological / missional companions
- *Ephesians 4:1-6*, seven-fold one
- *1 Corinthians 12:12-27*, body with many members
- *Acts 2:42-47; 4:32-37*, early-church visible unity

### People who developed the reading
- *John of Damascus*, patristic *perichoresis* foundation
- [Augustine](/codex/augustine/), patristic-Western love-as-Spirit reading
- [Cyril of Alexandria](/codex/cyril-of-alexandria/), Christological-hypostatic reading
- [Thomas Aquinas](/codex/thomas-aquinas/), medieval *circumincessio* development
- [John Calvin](/codex/john-calvin/), Reformed invisible-spiritual-unity reading

### Apologetic deployment
- [Evangelism](/codex/evangelism/), the missional-credibility framework
- [Hypocrisy](/codex/hypocrisy/), the negative-deployment defeater (the verse's prayer reveals the cost of Christian disunity)
- [Conversation Scenarios](/codex/conversation-scenarios/), §11 (wounded ex-church person), the unity-prayer makes sense of why disunity wounds so deeply

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## Quoted in

**Arguments and defeaters:**

- [Argument from Religious Experience](/codex/argument-from-religious-experience/)
- [Unitarian Oneness Binitarian Objection Defeater](/codex/unitarian-oneness-binitarian-objection-defeater/)

**Concepts:**

- [Christianity](/codex/christianity/)
- [Jesus Said](/codex/jesus-said/), via [John 17](/codex/john-17/)
- [Theosis](/codex/theosis/), via [John 17.21-23](/codex/john-17-21-23/)

**Lexicon:**

- [G1520 - heis](/codex/g1520-heis/), via [John 17.21-23](/codex/john-17-21-23/)
- [G4100 - pisteuo](/codex/g4100-pisteuo/)
- [H0001 - ab](/codex/h0001-ab/)

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