When Paul wrote to the Ephesians, he urged them “to walk in a manner worthy” of their calling (Eph 4:1). Explaining part of what that meant, Paul exhorts the Ephesians to be “eager to maintain the unity of the Spirit in the bond of peace” (Eph 4:3).
Paul doesn’t leave us without an explanation of what this unity in the Spirit looks like. He specifies seven marks of Spiritual unity (Eph 4:4–6). Each mark defines an essential belief that every church must agree on and unite around.
As Paul explains, “There is one body and one Spirit—just as you were called to the one hope that belongs to your call— one Lord, one faith, one baptism, one God and Father of all, who is over all and through all and in all.”
Notice the sevenfold repetition of “one.” Each repetition explains the unity of the Spirit that all Christians must confess. Paul here uses the number seven to emphasize the perfection or completion of Spiritual unity since the number seven often signifies completion in Scripture.
In light of all this, it is worth outlining what these seven marks of oneness are—these seven marks of the true church.
1. One body
When Paul asserts that there is one body, he means the Spiritual body of Christ. The church is that body. And importantly, the metaphor of body has real meaning. We are truly the body of Christ because the Spirit has united us to the flesh of Christ and to each other Spiritually, that is, by the Holy Spirit indwelling us.
Paul has already made these or similar points in Ephesians. For example, he defines the mystery of the Gospel as making the gentiles one body with Jewish persons: “This mystery is that the Gentiles are fellow heirs, members of the same body, and partakers of the promise in Christ Jesus through the gospel” (Eph 3:6).
Even earlier, he defined the body of Christ as a Spiritual body in which the Spirit dwells and Christ sits as the cornerstone:
For through him we both have access in one Spirit to the Father. So then you are no longer strangers and aliens, but you are fellow citizens with the saints and members of the household of God, built on the foundation of the apostles and prophets, Christ Jesus himself being the cornerstone, in whom the whole structure, being joined together, grows into a holy temple in the Lord. In him you also are being built together into a dwelling place for God by the Spirit. (Eph 2:18–22).
Our unity in Christ by “one Spirit to the Father” describes our trinitarian union with God that marks the sum of God’s redemptive work. God intended “to unite all things in him” (Eph 1:10) so that, among other things, “the church … is his body” (Eph 1:22–23).
The church as “one body” therefore receives the remarkable dignity of being “the fullness of him who fills all in all” (Eph 1:23).
In sum, when Paul speaks of one body, he signifies the reality that the church is Christ’s body because of the Holy Spirit who indwells us and unites us to Christ and to each other so that we may come to the Father.
Put simply, one body means that we have the Spirit, are in Christ, and ascend to the Father. And the body metaphor goes beyond mere rhetorical flourish since it is a reality that is based upon the Holy Spirit’s uniting work.
2. One Spirit
It should be clear now that one Spirit here refers to the Holy Spirit, that bond of love who mediates Christ to us, unites us to each other, and through Jesus brings us to the Father. Since the Spirit unites us to Christ, he brings us to Life.
Paul explains this connection to life in Colossians, a book with major parallels to Ephesians: “For you have died, and your life is hidden with Christ in God. When Christ who is your life appears, then you also will appear with him in glory” (Col 3:3–4). Our life becomes so entwined with Christ’s by virtue of our bodily and Spiritual union with him that he called our “life.” As Paul says elsewhere, “It is no longer I who live, but Christ who lives in me” (Gal 2:20).
This goes a long in explaining why Paul sees being filled with the Spirit as the key to our sanctification: “be filled with the Spirit” (Eph 5:18). How else can we be “a dwelling place for God by the Spirit” if we not filled by the Spirit (Eph 2:22)? But he does dwell us, and he must fill us.
And when that does not happen, we “grieve the Holy Spirit of God” (Eph 4:30) since he is now part of our body (“his Spirit [is] in your inner being” Eph 3:16), and sin grieves him!
3. One hope
All of us were dead in our sins “having no hope and without God in the world” (Eph 2:12; cf 2:1). But the Spirit makes us realize our hope (Eph 2:17–18). And that hope in the context of Ephesians is knowing the Father in Christ by the Spirit through making increasingly holy as the body of Christ (e.g., Eph 2:18–22).
Elsewhere, Paul fills in the blanks of how we come to know God in this way. Our hope thus includes not only our vindication at the resurrection but the resurrection of the dead itself. We will groan with creation until then. Yet at that time, we will see God face to face, no longer in a dim mirror but with the clarity that holiness will bring us.
4. One Lord
Creation moves to one goal: the unity of all people in the body of Jesus Christ. This was plan A. As Paul explains, God has made “known to us the mystery of his will, according to his purpose, which he set forth in Christ as a plan for the fullness of time, to unite all things in him, things in heaven and things on earth” (Eph 1:9–10). The word “mystery” is key here.
Paul continues to explain this mystery by writing:
“the mystery was made known to me by revelation, as I have written briefly. When you read this, you can perceive my insight into the mystery of Christ, which was not made known to the sons of men in other generations as it has now been revealed to his holy apostles and prophets by the Spirit. This mystery is that the Gentiles are fellow heirs, members of the same body, and partakers of the promise in Christ Jesus through the gospel” (Eph 3:3–6).
In short, the mystery now revealed is that God always intended to save all people by the free offer of the Gospel in Christ and by the Spirit. That salvation looks like bringing both Jews and gentiles into “the same body.” The effect of this is to fulfill “the eternal purpose that he has realized in Christ Jesus our Lord” (Eph 3:11).
To make the same point, Paul elsewhere explains that Christ “might create in himself one new man in place of the two” (Eph 2:15). This union brings us peace with God and each other through the cross of Christ (Eph 2:15–16). And this union places Christ as our head—the Lord of the church.
Yet his redemptive work goes beyond the church since it also makes him the Lord of all creation (Eph 1:15–23). Peter in Acts makes the same point: “God has made him both Lord and Christ, this Jesus whom you crucified” (Acts 2:36).
Our union with the Lord, by the way, explains how the cross forgives us since we share in the vindication of Christ through our union with him. In him, we are justified, sanctified, and (will be) glorified.
As Paul explains, “And because of him you are in Christ Jesus, who became to us wisdom from God, righteousness and sanctification and redemption” (2 Cor 1:30). And even more explicitly he writes, “For our sake he made him to be sin who knew no sin, so that in him we might become the righteousness of God” (2 Cor 5:21).
5. One faith
Faith here does not exactly refer to our subjective belief in Christ. It includes that. But here, as elsewhere (Jude 3), it means something like a “confession” or a “body of beliefs.” In this sense, the Spiritual offices that the Spirit bestows on the body of Christ help us “attain to the unity of the faith” (Eph 4:13).
By our confession of faith (that we are one Spiritual body in Christ), we will gain the unity of faith. This faith becomes a shield and protection to us (Eph 6:16). If we wear it, the devil will not be able to hurt us. Note: this defence involves the whole body of Christ as both the context of the book of Ephesians and the plural verbs in Ephesians 6 confirm.
6. One baptism
Christian baptism means baptism into the “name of the Father, of the Son, and of the Holy Spirit” (Matt 28:19). The word “name” here is singular. So the singular name of the one Father, one Son, and one Spirit alone constitutes Christian baptism.
We have no reason to believe that Paul had any other view. And given the extensive trinitarian themes in Ephesians as noted above and with great flourish in Ephesians 1:1–14, we can assume that he shared the evangelist’s view. Paul was a fully-orbed trinitarian Christian.
Baptism into the name of the Father, Son, and Spirit for the early church was both the beginning and end of worship. It was the beginning because the entrance into the church required a confession of the triune name. And the end because our worship leads us by the Spirit and in Christ to the Father.
7. One God and Father of all
The trinitarian implications of baptism and all subsequent worship come to head here in the seventh mark of oneness. Paul already underlined our confession in one Lord and one Spirit. Now we confess one “God and Father of all.”
Here Paul preserves the unity of God by writing “One God” while also the moreness of God by writing “Father.” The threeness and oneness of God or more usually the oneness of God and the divinity of Christ undergird much of the New Testament.
In 1 Corinthians, for example, Paul cites the Shema of Deuteronomy 6—Israel’s hallmark text for God’s oneness—while inserting both the Father and the Son into this confession of oneness: “yet for us there is one God, the Father, from whom are all things and for whom we exist, and one Lord, Jesus Christ, through whom are all things and through whom we exist” (1 Cor 8:6). Somehow there is one God, the Father, and one Lord (a consistent title for God in the OT), Jesus Christ. And both persons are involved in creation.
Creation comes from the Father through the Lord Jesus Christ. So both the Father and Son play a role in creation and despite all of this, there remains one God (cf. John 1:1–3). Paul here without apology can affirm the oneness of God while distinguishing the Father and the Lord.
In other words, Paul in Ephesians perceives our Spiritual unity as centered on the triune faith that makes us one body through the Spirit who forges a union with us and Christ so that we can come to the Father.
At this point, we may no longer want to call Paul’s words here seven marks of church unity. Instead, these are seven visions of one Spiritual unity. Each affirmation in these verses uses the word “one,” and Paul understands each statement as “the unity of the Spirit in the bond of peace” (Eph 4:3).
It may now be clearer as to how it is the unity of the Spirit since each of the seven “ones” overlap so closely—each touch on our Spiritual indwelling, our union with Christ and with each other by the Spirit, and our movement to the Father.
Our oneness is both real in that Christ truly and Spiritually unites us to Christ and to each other, yet it is also something to grow in because the “bond of peace” requires that the Spirit fill us so that we can attain the fullness of our unity in the Spirit.
This oneness since it is a Spiritual union by necessity means that we not only are united as one local church but to all churches who share the same Spiritual oneness. This is because the Spirit is not located in one place only! The heavens cannot contain him, and he unites us to Christ and to each other across time and space.
There is a universality to the Christian faith that we cannot ignore. We are all baptized into one Spirit (1 Cor 12:13) so that we all confess that Jesus is Lord (1 Cor 12:3). The bread we all partake of is “a participation in the body of Christ” (1 Cor 10:16). This oneness means that churches in Jerusalem, Macedonia, and Corinth share in the same struggles (2 Cor 8–9). In fact, they share spiritual and material oneness (Rom 15:26).
There is a beautiful oneness to Christianity that must be pursued. And the reality of oneness requires the action one of oneness. We must thus press on to walk in “a manner worthy” of our calling (Eph 4:1) and to be “eager to maintain the unity of the Spirit in the bond of peace” (Eph 4:3).
This happens by our mutual confession of “one body and one Spirit—just as you were called to the one hope that belongs to your call— one Lord, one faith, one baptism, one God and Father of all, who is over all and through all and in all.”