Dark energy is some kind of cosmic force causing the universe to expand. It makes up about 75% of the universe, and so dynamically holds it all together that NASA calls dark energy the “glue” of the universe.

The truth is that nobody really knows what “dark matter” is — but it seems important. “There’s something real, but invisible, and central to the world in which we live, something that permeates all we see and know, and not only do we rarely talk about it, but we’re not even sure where to start.”

Those are the words of pastor Rankin Wilbourne in his new book Union with Christ: The Way to Know and Enjoy God, one of the best books of 2016.

Wilbourne asks, “If you’re wondering: Why do I need to know about union with Christ? Is it really necessary? I’ve gotten along fine thus far without understanding it. Perhaps you feel that union with Christ is like dark energy — invisible, mysterious, impractical, because it’s true that you can get through your whole life having never once thought about dark energy. And most of us do” (115).

And yet, manifold glories await the Christian who opens the Bible in search of understanding union with Christ. What does it mean that we are united to Christ, that our union is the “dark matter” glue of the Spirit connecting us to him?

I recently began a search to discover more about the mystery of our union with Christ, to better understand this glue that binds the redeemed to the Redeemer. The first question on my list is about union and our personal suffering. What’s the connection?

Does Union Add Suffering?

More specifically, does our union with Christ merely sanctify our inevitable suffering? Or does union with the suffering Christ bring new and deeper suffering? This is a question I’ve had for a long time, especially from studying Paul’s letters to the Corinthian church. In the context of explaining his own personal suffering, Paul uses language like:

• “As we share abundantly in Christ’s sufferings, so through Christ we share abundantly in comfort too.” (2 Corinthians 1:5)

• “. . . always carrying in the body the death of Jesus, so that the life of Jesus may also be manifested in our bodies. For we who live are always being given over to death for Jesus’ sake, so that the life of Jesus also may be manifested in our mortal flesh.” (2 Corinthians 4:10–11)

• “He was crucified in weakness, but lives by the power of God. For we also are weak in him.” (2 Corinthians 13:4)

In Christ we “share his sufferings” (Philippians 3:10). Even Peter calls us to “rejoice insofar as you share Christ’s sufferings, that you may also rejoice and be glad when his glory is revealed” (1 Peter 4:13).

So again I ask: Does our glorious union with Christ merely sanctify our inevitable suffering, or does union with the suffering Christ bring with it the addition of new and deeper suffering into our lives?

Suffering Is Inevitable and Meaningful

“Well, the answer is yes — both,” said Wilbourne in a recent interview. “On one hand, we are united to the one who is called the Man of Sorrows, well acquainted with grief (Isaiah 53:3). We are united to the One whose whole life was perpetual crucifixion. We are united to the One who calls us to take up our cross (Luke 9:23). And the New Testament makes it clear in several places that you cannot know this Christ apart from suffering.”

“On top of this, you will suffer for knowing Christ. ‘I will show him how much he must suffer for the sake of my name’ (Acts 9:16). That is not just true for Paul. That is true for any of us who want to count the cost of following Christ. The New Testament draws a link that we would be slow to draw: You cannot know Christ apart from suffering.”

Suffering is an essential part of our union with the suffering Christ. And yet “the Bible never romanticizes suffering, and it doesn’t minimize it either,” he reiterated. “And there’s no call to stoical resignation. At the same time, the Bible makes it clear that if we are united to Christ, suffering will be inevitable for every human being. Union with Christ makes clear that God redeems our suffering, not only to introduce us to ourselves, but also to introduce us to him.”

“Suffering is one of the means that God uses for us to know his heart,” Wilbourne said, alluding to the book Walking with God through Pain and Suffering, where Tim Keller writes: “Christianity teaches that, contra fatalism, suffering is overwhelming; contra Buddhism, suffering is real; contra karma, suffering is often unfair; but contra secularism, suffering is meaningful. There is a purpose to it, and if faced rightly, it can drive us like a nail deep into the love of God and into more stability and spiritual power than you can imagine” (30).

“The suffering Christian is being driven to the heart of God and conformed to the image of Christ,” Wilbourne concludes. “So yes, Christ sanctifies our inevitable suffering. And knowing Christ will bring with it new and deeper suffering.”

Conforming to Christ

I posed the same question to Sinclair Ferguson, author of the new book Devoted to God: Blueprints for Sanctification. Union with Christ has been a cornerstone of Ferguson’s ministry over the decades.

So does union with Christ sanctify inevitable suffering or bring more suffering with it?

He replied with a similar answer: yes and yes.

“We live in this fallen world and we share in man’s common ailments and struggles, disasters and tragedies. All of this is what you have called ‘inevitable suffering,’” Ferguson said. “But because we experience it in Christ under the aegis of the purposes of the heavenly Father working everything together for the ultimate good, and conforming us to the image of his Son — this suffering is a product of our union (Romans 8:28–30). We are becoming like the one with whom we most intimately live, so we can say that as the Christian shares in the general sufferings of the human lot, there is something distinctive about the way he or she experiences them, because the sufferings are received by the Christian as transforming and sanctifying in the hands of the heavenly Father.” The “inevitable suffering” for the Christian now works toward one glorious end.

So yes, our union Christ sanctifies all our “inevitable suffering” in this fallen world, but it also brings deeper suffering, too. “But this is not necessarily different suffering or greater suffering or even lesser suffering” Ferguson says. “As we live our lives in Christ, thrust upon us — under the providence of God, and often in the hands of others — comes another layer of suffering. And that layer of suffering is related both to the fact that we are so profoundly counter-cultural in our lifestyle, and also to the fact that the gospel has sensitized us to the horror that sin effects in the world. So we experience a kind of suffering because we are Christians with new behaviors and sensitivities.”

Weakness: The Path to Strength

If suffering is a sense of weakness, then in our weakness we find our power, as Paul says in 2 Corinthians 12:1–10. This concept is different than saying that when we feel our own weakness, Christ is strong. “I think people read this passage as though Paul is saying that we are weak in ourselves but strong in Christ. But he’s saying that our weakness is also a function of our union with Christ, because we share in his distinctive sufferings, not on the level of their atoning power, but in terms of the model of their fruit-bearing character.”

Take 2 Corinthians 4:7–12. Paul bears in his body the marks of our Lord Jesus. Death works in him. Life works in others. Or take Paul’s words to the Colossians: “Now I rejoice in my sufferings for your sake, and in my flesh I am filling up what is lacking in Christ’s afflictions for the sake of his body, that is, the church” (Colossians 1:24). “I think that Paul is saying: I have experienced union with Christ in terms of suffering that comes to me because I am united to Christ. And he expects more of it to come.”

Death: The Path to Life

Ferguson believes that the life and death of Stephen, stoned to death in the presence of Paul (then Saul), was an unforgettable illustration for the apostle (Acts 7:54–8:1). It was Stephen’s death that helped bring about Paul’s spiritual life. “John Calvin said from the beginning that God has so constituted the church that death is the way to life, and the cross is the way to victory. Union with Christ, I think, then grinds that into the lenses through which we see absolutely all of the suffering of our lives.”

So yes, our union with Christ sanctifies our inevitable suffering in this world. And yes, our union with Christ also brings with it a greater sting in our suffering, as we live contrary to the world and as we see the ravages of sin in this world and among those we love.

It is God’s will that we share in the momentary suffering of Christ, for a little while longer. “Beloved, do not be surprised at the fiery trial when it comes upon you to test you, as though something strange were happening to you. But rejoice insofar as you share Christ’s sufferings, that you may also rejoice and be glad when his glory is revealed” (1 Peter 4:12–13).