Union with Christ: A Brief Introduction

John Owen (1616-1683) said, “That there is such a union between Christ and believers is the faith of the catholic church and has been so in all ages.”

Not only does Owen’s comment dissuade us from regarding this doctrine to be negligible and of optional interest, his comment challenges us not to be found as theological innovators via absentmindedness. We must not forget union with Christ. 

Every spiritual benefit we believers receive – justification, adoption, and sanctification – flow to us out of the person of Jesus Christ. These benefits do not exist alone, each standing off in its silo waiting to be rewarded to the elect if they rap the secret knock upon each door. On the contrary, all the benefits of our salvation exist in a living person and flow to us like the vital sap which exists between vine and branches (John 15:5).

The righteousness imputed and applied to us for justification is the righteousness of a person, Jesus our Lord. The liberties, privileges and name put upon us in adoption are those which belong to a person, Jesus our Lord (Gal. 4:6). The holiness which slowly renovates us in sanctification is the holiness of a person, Jesus our Lord (Rom. 8:29). The Holy Spirit takes these from him and makes them mine. Only life begets life.

So we see, union with Christ compels us to keep a person-centered understanding of salvation not an exclusively benefit-centered understanding. The old trope “salvation by doctrine” is rightly exposed and obliterated by the doctrine of union with Christ.

Those teaching the Reformed faith in the churches of Christ should not wish for students to long dwell in a piety limited to knowing the correct definitions (sola definitio) of justification, adoption, sanctification, etc. Such definitions must never ever be avoided, but none understand these things sufficiently until they are understood as belonging to a living person who is to be worshipped and adored for possessing such riches and giving us possession of the same through Spirit wrought union with him.

In saying this, we do not mean to diminish the importance of the ordo salutis. A robust doctrine of union with Christ does not diminish a robust prioritizing of justification before sanctification. As grandfathers everywhere have said, “We can walk and chew gum at the same time.”

We can assert that sanctification is never antecedent to justification while also asserting that the foundation of the forensic (justification) is union with Christ. In other words, our mystical organic union with a person, our Lord Jesus Christ, encompasses all the benefits of salvation found in the ordo salutis. Christ has always been the source, the circumference and the center of our life in God. As John Murray said, “Union with Christ is really the central truth of the whole doctrine of salvation.”

Our union with Christ should be understood as having – as Berkhof taught – an eternal, an objective and a subjective reality.

The eternal reality of this union was in the covenant of redemption, the pactum salutis. Before the foundation of the world the Father covenanted with the Son to redeem and constitute a new humanity. The whole church was chosen, given and united to the Son as representative Head (John 10:29, Eph. 1:4). This is known as the federal union of Christ, an astounding wonder of sovereign grace whereby we had a union privilege with Christ by covenant before we had an actual union with Christ by faith. There was no way we would not be saved!

The objective reality of this union then was in the incarnation of the Son and all which was accomplished by it in history (Heb. 2:14). In an objective sense what he did and suffered we did and suffered in him. As we were offspring of sin from union with the first Adam, we would be offspring of righteousness from union with the second, Christ. So, he says: “Behold, I and the children God has given me” (Heb. 2:13). Being united to our flesh we were united to him objectively in his death, in his resurrection, and in his ascension to the heavenly places of dominion. Everything we needed to accomplish was accomplished in union with him, it just needed application to each of us. Which brings us to the subjective reality of this union.

The subjective reality of union with Christ, what some call our intimate or vital or existential union, is the completion of the union. The Holy Spirit, in due time, applies to us and puts into our possession all which already belongs to us by virtue of the objective union we had with Christ in his accomplishments. By the Holy Spirit we are called, regenerated, given faith and so enabled to appropriate all spiritual benefits in Christ.

In Christ. Two words. Such is the ubiquitous shorthand the apostle Paul uses for this magnificent doctrine throughout his letters. It is simple enough for training children and profound enough for lifelong study and meditation.

John Hartley has been pastor of Apple Valley Presbyterian Church since 2010, having previously been a pastor for 10 years in Vermont. He is a Wisconsin native and a graduate of University of Wisconsin-Milwaukee as well as Dallas Theological Seminary. John lives with his wife Jen and their five children.