Surveying Sanctification: Union with Christ

That holiness of life which the Christian has from God and before God and for God is not sourced nor drawn from even the best doctrinal formulations – as essential as they are to our faith. Nor is holiness of life sourced or drawn from moral transformation – as essential as it is to living out our faith. Holiness of life is drawn from Christ, who alone is “life-giving Spirit” (1 Cor. 15:45).

You see, we may have doctrinal formulations and moral pursuits but still be outside of Christ. How? Because the life Christ bestows does not spring up from the work of our own hands nor does it spring out of our own minds. True life is from above not below. It comes from heaven in the person of Jesus Christ (John 6:33).

The Westminster Larger Catechism asks, “What is that union which the elect have with Christ?” (Q. 66).
Answer: “The union which the elect have with Christ is the work of God's grace, whereby they are spiritually and mystically, yet really and inseparably, joined to Christ as their head and husband; which is done in their effectual calling.”

When the soul dead in sin is effectually called, the Spirit bestows saving faith and puts us into Christ and puts Christ into us (John 14:20). “In him” is the apostle Paul’s ubiquitous shorthand for the doctrine of union. The Spirit takes what belongs to Christ and gives it to us. We are not just given the Spirit, as it were, but Christ gives us himself through the Spirit. Because we now have him, the many wonderful benefits of his mediation become ours.

Again, the Westminster Larger Catechism asks: “What is the communion in grace which the members of the invisible church have with Christ?” (Q. 69). Answer: “The communion in grace which the members of the invisible church have with Christ, is their partaking of the virtue of his mediation, in their justification, adoption, sanctification, and whatever else, in this life, manifests their union with him.”

Union with Christ reminds us we cannot lay hold of one benefit of Christ without receiving the others. We cannot come to Christ for justification and somehow sneak away without sanctification. To have one benefit is to have Christ. To have Christ is to have all benefits. The benefits of justification and sanctification are, of course, distinct from each other, but they are not distinct from the one communion in grace the believer has by virtue of union with Christ. 

J. Todd Billings put it very well, saying: “in justification, the Spirit unites the believer to Christ, revealing the pardon of the Father; in sanctification, the Spirit empowers believers to participate in Christ, growing in Christlikeness” (Calvin, Participation, and Gift: The Activity of Believers in Union with Christ,” p. 188).

Because of union with Christ, sanctification must never be abstracted from the Christian experience. Only life begets life. Sanctification is not something we pick up and put on when the mood strikes us. It is fundamental to our identity in Christ.

Now we can be sure we have abstracted sanctification as a stand-alone thing when we think of holiness in the exclusive terms of imitating Christ. In this construal of sanctification, holiness becomes the pursuit of an imagined version of our future religious selves. The unexpected failure of this abstraction, however, is how it devolves into a religious humanism that fails to apprehend by faith our gracious participation in the resurrection and ascension of Christ. As Michael Horton said: “believers bear fruit that is not the result of their imitation of Christ’s life but of their being incorporated into Christ and his eschatological resurrection-life in the Spirit” (The Christian Faith, p. 591).

When our interest in sanctification is rightly regarded as a manifestation of union with Christ, we will, by faith, reckon ourselves a new creation in Christ. We will see sanctification as necessary to who we are in Christ. We will see sanctification as having a vitality and privilege of its own, a benefit of the risen and enthroned Christ, already at work in us even as it beckons us. In this way true sanctification is the believer being laid hold of by Christ and laying hold of Christ themselves, by faith, that eschatological identity we now possess as members of Christ our living head.

“We ought not to separate Christ from ourselves or ourselves from him.  Rather we ought to hold fast bravely with both hands to that fellowship by which he has bound himself to us. So the apostle teaches us: ‘Now your body is dead because of sin; but the Spirit of Christ which dwells in you is life because of righteousness’” (Romans 8:10; Calvin, Institutes, 3.2.24).

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.