One objection the Reformers faced was that their doctrine of justification by faith alone eliminated the need for good works and sanctification and thus robed people of the motivation for these necessary elements of the Christian life. Nevertheless, despite accusations to the contrary, Luther championed justification by faith alone while making clear that true faith would bear the fruit of good works. But it is was John Calvin a few years later who would provide greater clarity on how to understand the relationship between justification and sanctification.
Although justification and sanctification are distinct—the former is a point-in-time declaration apart from works received by faith alone, and the latter a process that continues throughout the believer’s life that involves good works—these two theological realities cannot be separated. That is, where true justification occurs, sanctification inevitably and immediately follows. Calvin helps us understand how this can be by placing justification and sanctification together within the doctrine of union with Christ.
We must now examine this question. How do we receive those benefits which the Father bestowed on his only-begotten Son—not for Christ’s own private use, but that he might enrich poor and needy men? First, we must understand that as long as Christ remains outside of us, and we are separated from him, all that he has suffered and done for the salvation of the human race remains useless and of no value for us. (Institutes III.1.1).
…Peter says that believers have been “chosen in the sanctification of the Spirit unto obedience and the sprinkling of the blood of Christ [1 Peter 1:2]. By these words he explains that, in order that the shedding of his sacred blood may not be nullified, our souls are cleansed by the secret watering of the Spirit. For the same reason, also, Paul, in speaking of cleansing and justification, says that we come to possess both, “in the name of…Jesus Christ and in the Spirit of our God” [1 Cor 6:11] (Institutes III.1.1).
By partaking [of Christ], we principally receive a double grace: namely, that being reconciled to God through Christ’s blamelessness, we may have in heaven instead a Judge a gracious Father; and secondly, that sanctified by Christ’s spirit we may cultivate blamelessness and purity of life (Institutes III.11.1)
Scripture teaches us that when the believer places his faith in Jesus Christ alone for salvation, he is immediately united to him: the believer is now “in Christ.” This phrase “in Christ” is one of Paul’s favorite to describe the present state of believers (see Rom 8:1; 2 Cor 5:17; 12:22; Gal 3:28; 5:6; Eph 1:3; 2:6-10, 13). The fruit of this union is justification (we are declared righteous before God because we now possess Christ’s righteousness) and sanctification (we are immediately cleansed and continue to grow in holiness because we are vitally connected to Jesus Christ in a spiritual relationship).
The question of good works and their relationship to justification, then, is no longer a problem because Calvin helps us view our salvation concretely and holistically rather than abstractly and one-dimensionally. I am not accusing Luther of viewing salvation one-dimensionally. But it is possible—and history and our contemporary discussions on justification bear this out—to view our salvation exclusively in terms of justification at the expense of other soteriological elements, like sanctification and the necessity of good works.
Drawing justification and sanctification under union with Christ, while maintaining the vital distinction between these two aspects of our salvation, preserves the relational reality of our salvation while helping us avoid reductionism. Specifically, union with Christ emphasizes that we are justified by faith alone in a Person, and it is through and as a result of our relationship with this Person that we bear the fruit of holiness and good works. Justification and sanctification are kept together while remaining distinct, and Christ remains at the center of our salvation.