The doctrine of union with Christ is the rock-bed foundation of soteriology. Sinclair Ferguson writes in his theology of the Holy Spirit, “Every facet of the application of Christ’s work ought to be related to the way in which the Spirit unites us to Christ himself” (Ibid. 100). Elsewhere, John Murray boldly writes, “Union with Christ is…the central truth of the whole doctrine of salvation…it underlies every aspect of salvation” (Redemption–Accomplished and Applied, p. 201, 205). Without a doubt, even conservatively stated, this doctrine is vital to understanding our salvation.
With that said, the all-important question becomes, What is union with Christ? Wayne Grudem defines union with Christ as follows: “Union with Christ is a phrase used to summarize several different relationships between believers and Christ, through which Christians receive every benefit of salvation” (Systematic Theology, p. 841). Our salvation can be and should be viewed through the lens of our union with Christ. Simply put, this doctrine refers to the fact that sinners can become one with Christ by faith. This results from a work of the Spirit in regeneration. And by our God-initiated faith, we become united to the object of our faith and as a result, all of his accomplishments become ours. We gain access to the glories of Christ by our union with him.
To be “in Christ” [εν Χριστω] means to share in all that Christ has accomplished (Sinclair Ferguson, The Holy Spirit, p. 106).
Think about this! This means that the whole of the “golden chain” of salvation, from eternal election to final glorification, is ours. Ferguson argues in his work, The Holy Spirit, that we actually take part, at least forensically or economically, in every single aspect (or link) of our salvation. While we experience each of these aspects of salvation at different points in history, they should be viewed as one eschatological event, namely the resurrection of Christ, that we take part in through union with Christ. This is because in our union with Christ, we share in all that he has accomplished.
Louis Berkhof would agree:
By this union believers are changed into the image of Christ according to his human nature. What Christ effects in his people is in a sense a replica or reproduction of what took place with him (Louis Berkhof, Systematic Theology, p. 451)
This implies that we should think of Christ as being justified, adopted, sanctified, and glorified. While it is typical for us to understand Jesus as being glorified, we (or at least I) typically do not understand Christ as being justified, adopted, or sanctified. However, Ferguson suggests that Jesus experienced all of these aspects of salvation through his resurrection. I find this to be both a compelling and edifying way to understand union with Christ that in turn effects our understanding of every other aspect of salvation. The facets of salvation, when viewed like this, are no longer primarily viewed subjectively and individualistically, but more cosmically and objectively in Christ. Now, I do not take Ferguson to be saying that Jesus was sinful and in need of salvation from the wrath of God. Instead, he is presenting Jesus as the Initiator, active Worker, and Foundation of our salvation from the wrath of God. Ferguson is arguing that we are justified, adopted, sanctified, and glorified because of our union with Christ. This is a refreshing and high way of thinking about salvation. And I love Ferguson’s Christological lens. He roots his discussion in Pauline theology:
In Paul’s exposition of the gospel, the categories [i.e. justification, adoption, sanctification, and glorification] used to describe the application of redemption to the believer are the categories which explicate the meaning of Christ’s resurrection. In other words, the application of redemption to us is rooted in the application of redemption to Christ (The Holy Spirit, 104).
I agree with Ferguson because of his theological and Christological exposition of the biblical witness to the historical resurrection of Christ. This was a fresh and joyous discovery for me. There is a uniquely God-glorifying and Christ-exalting element to thinking about my justification as being the result of my union to Christ’s justification. There is great comfort in the thought that my adoption as a son of God is the direct result of the adoption of the Son of God by his resurrection. There is tremendous confidence in Christian living that flows from thinking of my sanctification as resulting from Christ’s sanctification. And there is an unshakeable hope that settles and brings a a tranquil river of peace to my heart and soul when thinking of my glorification finding its root in Christ’s glorification. The hope and confidence in my salvation is not grounded in merely an idea, but in a historical reality and theological truth.
The resurrection of Jesus is viewed by Paul as his:
Great indeed, we confess, is the mystery of godliness: He was manifested in the flesh, vindicated by the Spirit [εδικαιωθη εν πνευματι]…(1 Timothy 3:16)
Having been made sin in his death, in his resurrection he was declared as our representative to be (what he in fact always was personally) righteous (Ferguson, The Holy Spirit, 104-105).
…he was declared to be the Son of God in power according to the Spirit of holiness by his resurrection from the dead, Jesus Christ our Lord…(Romans 1:4)
His resurrection…constitutes him messianic Son of God with power; in it he is adopted as the Man of the new age (Ibid. 105).
We know that Christ, being raised from the dead, will never die again; death no longer has dominion over him. For the death he died he died to sin, once for all, but the life he lives he lives to God. So you also must consider yourselves dead to sin and alive to God in Christ Jesus (Romans 6:9-11).
Paul writes this in the context of teaching on sanctification. What Paul does in verses 9-10 is set the stage for our sanctification. In other words, and more appropriately, Paul grounds the sanctification of all who are in Christ, the one who was raised after dying to sin, in the sanctification of this risen death-defeater. Because of Jesus’ sanctification and our union with him, we must consider ourselves dead to sin and alive to God in Christ Jesus (Rom. 6:11).
In his death Christ came under the dominion of sin; in his resurrection he was delivered from that dominion. This deliverance is the foundation of sanctification…” (Ferguson, Ibid. 105)
But in fact Christ has been raised from the dead, the firstfruits of those who have fallen asleep…So it is with the resurrection of the dead. What is sown is perishable; what is raised is imperishable. It is sown in dishonor; it is raised in glory. It is sown in weakness; it is raised in power. It is sown in a natural body; it is raised a spiritual body. If there is a natural body, there is also a spiritual body (1 Corinthians 15:20, 42-44).
[Jesus Christ] will transform our lowly body to be like his glorious body (Philippians 3:21).
As a result of his resurrection, Christ was raised in glory and all who are united to him by grace through faith will one day be raised in glory in the likeness of our Savior and Lord Jesus Christ (Rom. 8:29).
The doctrine of union with Christ is one of the most joyous doctrines of the Christian faith and all other aspects of the doctrine of salvation should be interpreted, understood, and studied in light of this great truth. We are united to the Elect One. We are united to the Justified One who was justified to be our representative–the last Adam who did what the first Adam failed to do, which is become our Prophet, Priest, and King. We are united to the adopted Son, who is the foundation of our adoption as sons (and daughters). We are united to the Holy One who grounds both our definitive and progressive sanctification. We are united to the Glorified One and in him we currently reign with him, and will do so forever. Viewing our salvation in the paradigm of the redemption that is in Jesus Christ and his work breeds immovable certainty, unwavering confidence, unshakeable hope.
To be “in Christ means to share in all that Christ has accomplished. More specifically this means that those who are united to the risen Christ share in his justification, adoption, sanctification and glorification. Just as in the case of Christ these are all aspects of the single eschatological event of his resurrection and in him are simultaneous and inseparable, so with us. It follows that, in the case of believers, to be united to Christ by the Spirit means to share in his justification, adoption, sanctification and glorification. In Christ these are ours immediately, eschatologically and simultaneously.
Of course, justification, adoption, sanctification and glorification are distinct categories of the application of redemption and should never be confused. But they are not to be viewed as separate events; they are aspects or facets of the one event of our union with Christ in his risen glory, effected by the power of the Spirit and worked out progressively through the Spirit’s ongoing ministry (Ferguson, The Holy Spirit, 106).
If all of this is true (and it is), then we are left with only one short, but glorious exhortation. And I will allow the great theologian, John Calvin, do the exhorting:
In short, since rich store of every kind of good abounds in him, let us drink our fill from this fountain, and from no other (Institutes, II.16.9).
Drink deep and drink often from the fountain of ever-flowing joy in whom you have life!