The jewel and the sun

The Jewel and the Sun: Justification and Union with Christ according to the Reformers

First published in Moore Matters Winter 2023

Jewellery and sunshine. These are two powerful images used by the Reformers to describe our relationship with God by his grace. The reality they illustrate is still vital for us to remember today.

The big issue: How can God justify the ungodly?

One key issue the Reformers were wrestling with was understanding and explaining justification by faith. “To justify” is an action of a judge in court. It means to declare that a defendant is righteous. But when we face God, our creator and ultimate judge, we’re not righteous. We’re sinners. We don’t deserve God to declare us righteous. Yet wonderfully, as Paul writes in Romans:

And to the one who does not work but believes in him who justifies the ungodly, his faith is counted as righteousness. (Rom 4:5–6)

God justifies us by faith. This is both immensely comforting and profoundly problematic. It’s immensely comforting because we’re all ungodly sinners. We need God to justify us. Otherwise, we would never be able to stand in the face of his judgment and never receive eternal life! But it’s also a huge theological problem. After all, God is meant to be a righteous judge. By rights, a righteous judge should never justify unrighteous sinners (see, e.g., Ex 23:7; 1 Kings 8:32). So how can God both be a righteous judge while also declaring unrighteous people righteous (see Rom 3:26)?

Inherent righteousness?

A standard answer to this question given by the Roman Catholic church was that justification involves God’s grace actually making us righteous people. God imparts to us inherent righteousness. The modern Catechism of the Catholic Church puts it this way: “Justification is not only the remission of sins, but also the sanctification and renewal of the interior man” ( That means we can and should work to “merit for ourselves and for others the graces needed for our sanctification, for the increase of grace and charity, and for the attainment of eternal life” (

The Reformers realised this view had a huge problem. We can never be sure if we’re righteous enough to be saved from God’s judgment. Even though Jesus has died for our sins, we still need God’s Spirit to graciously work in our lives to produce enough grace and love to merit eternal life.

Imputed righteousness

As the Reformers carefully read key biblical texts (e.g., Rom 3:21–22; 4:3–8; 5:17–19; Phil 3:9; 2 Cor 5:21; 1 Cor 1:30), they saw that no righteousness flowing from us and our works can satisfy God’s holy and righteous requirement. They saw that God justifies us, not by imparting righteousness to us, but by imputing Christ’s righteousness to us. This means God reckons or counts Christ’s “alien” righteousness to us as if it is our own righteousness, even though it’s not.

But this seems to create a problem. The imputation of Christ’s alien righteousness can sound like a trick or a legal fiction. How can this “alien” righteousness really be counted as ours?

According to the Reformers, the answer is that we are united with Christ by the Holy Spirit through faith. The Spirit brings us to faith in Christ. This faith truly unites us to Christ. That means everything that belongs to Christ is ours, including Christ’s righteousness.

Martin Luther (1483–1546)

In Martin Luther’s lectures on Galatians, he uses the image of a jewel in a ring to explain how union with Christ is foundational to justification by faith. He writes:

Here it is to be noted that these three things are joined together: faith, Christ, and acceptance or imputation. Faith takes hold of Christ and has Him present, enclosing Him as the ring encloses the gem. And whoever is found having this faith in the Christ who is grasped in the heart, him God accounts as righteous. (Luther, Lectures on Galatians 1535, on Gal 2:16)

This righteousness is grounded firmly in Jesus’ death on the cross, where he took our sins on himself. As Luther had said earlier, expounding Galatians 2:21:

His sins are no longer his; they are Christ’s. … Again, Christ’s righteousness now belongs not only to Christ; it belongs to His Christian. (Luther, Lectures on Galatians 1519, on Gal 2:21).

For Luther, believing in Christ is like putting on a ring. When you have the ring on your finger, you also have the gem that the ring encloses. That gem is Christ, who died for our sins and rose from the dead. When we’re united to Christ by the Spirit through faith, we have Christ himself. So we truly have Christ’s righteousness and all the other blessings of the Christian life. God justifies us, not on the basis of our own righteousness that God imparts to us, but on the basis of Christ’s righteousness that God imputes to us.

John Calvin (1509–1564)

John Calvin clarified and deepened this Reformation understanding of justification through “the Holy Spirit” who “is the bond by which Christ effectually unites us to himself” (Institutes 3.1.1). Union with Christ means his righteousness is imputed to us:

[M]an is not righteous in himself but because the righteousness of Christ is communicated to him by imputation. … You see that our righteousness is not in us but in Christ, that we possess it only because we are partakers in Christ. (Calvin, Institutes 3.11.23)


[J]ustified by faith is he who, excluded from the righteousness of works, grasps the righteousness of Christ through faith, and clothed in it, appears in God’s sight not as a sinner but as a righteous man. (Calvin, Institutes 3.11.2)

Union with Christ by the Spirit through faith also helps us to understand the connection between justification and sanctification (i.e., living a godly Christian life). Calvin explains this by comparing Christ to the sun:

[A]s Christ cannot be torn into parts, so these two which we perceive in him together and conjointly are inseparable—namely, righteousness and sanctification. … But if the brightness of the sun cannot be separated from its heat, shall we therefore say that the earth is warmed by its light, or lighted by its heat? Is there anything more applicable to the present matter than this comparison? The sun, by its heat, quickens and fructifies the earth, by its beams brightens and illumines it. Here is a mutual and indivisible connection. (Calvin, Institutes 3.11.6)

The sun provides two things: light and heat. They’re not the same thing, but you never have one without the other. The same is true with justification and sanctification. If you have Christ, you have it all.

The joy and power of union with Christ

This is the great joy and power of the Reformers’ theology of grace. Justification is not about our work. In fact, ultimately, it’s not even about our faith. It’s not about us at all. Instead, it’s all about Christ: his life, death and resurrection. Everything we have—justification, sanctification, and all the other blessings of the Christian life—comes through union with him by the Spirit through faith.

Knowing this keeps our eyes and our hearts constantly focused on Christ—the jewel and the sun—who provides us with everything we need, now and into eternity.