I’M AN ACADEMIC by profession, literally, a professor. I’m supposed to know stuff. Lots of stuff. I teach and preach and write and counsel. And I hope that, in the final analysis, God will one day be able to say that I’ve been more helpful than not.

But there are still times when I feel like I know nothing at all. Trust me, you can be in academia for decades and still suffer impostor syndrome, still have that vague fear that sooner or later you’re going to say something really stupid and make people wonder how you got your job. Why do I get to talk about this stuff, you ask yourself, when there are other people who know it so much better than I do?

And then there are the things that for all our careful research, painstaking analysis, and impressive theories we will never fully understand anyway. That’s not to say that it’s wrong to try. Therapists may understand enough about a problem to be able to help, without having to understand everything about the person and why they do the things they do. Pastors and teachers can understand enough about Scripture to point people to God, without fully understanding everything they teach.

Paul’s letter to the Colossians, as we’ve seen, is filled with lofty language that paints a cosmic portrait of Jesus as the Christ. The apostle can say, for good theological and pastoral reasons, that the fullness of God resided in the man Jesus. But will anyone, including the apostle himself, ever truly understand all that this means? We will never fully comprehend God, let alone the idea of God’s fullness in a mortal body. If you really try to think about it, it can make your head spin.

It’s for situations like these that some of us have learned to take refuge in the phrase, “It’s a mystery,” whenever we reach the limits of our knowledge. Said with the appropriate gravity, it’s a profession of ignorance and wisdom at the same time: I can’t answer your question, but that’s because the answer is too profound for mere mortals like you and me. Said flippantly and with a shrug of the shoulders, it can be a way of saying, Nobody really knows, okay? We’re just supposed to believe it and not ask questions.

Paul, too, uses the language of “mystery.” He’s told the Colossians that he rejoices in his suffering, because he knows it to be part of his calling as an apostle to serve the church. Then he continues:

I have become its servant by the commission God gave me to present to you the word of God in its fullness—the mystery that has been kept hidden for ages and generations, but is now disclosed to the Lord’s people. To them God has chosen to make known among the Gentiles the glorious riches of this mystery, which is Christ in you, the hope of glory. (Col 1:25-27, NIV)

In biblical usage, the word “mystery” typically refers to the plans and purposes of God, which by the very nature of the case will always be more far-reaching and complex than is possible for us to comprehend. Paul uses the word twice here to refer to the fullness of the gospel message.

But note how he uses the word. True, as he says in verse 26, the mystery “has been kept hidden.” But now it’s been “disclosed” — the word could also be translated as “revealed,” or “made manifest.” Then in verse 27 he says it again in different words: God has made the mystery known. Moreover, he has made it known “among the Gentiles” — itself a surprise to many Jews! — and Paul himself has been an important part of that work.

Paul’s emphasis, in other words, is not to say that the mystery is unknowable. Nor is it to say, as the Gnostics might have it, that God reveals esoteric truths to only a select few. No. Even if the purposes of God are by nature mysterious to humans, God has graciously chosen to make them known, to reveal them in all their depth and richness.

And what is this mystery? Just this: “Christ in you, the hope of glory.”

. . .

PAUL GREETED THE Colossians in verse 2 by calling them “the faithful brothers and sisters in Christ.” And as I suggested earlier, it’s because they’re in Christ that they can be holy and blameless in God’s sight.

But Christ is also in them, which is probably another way for Paul to say that the Holy Spirit is in them. We might think here of how Paul wrote of his imprisonment to the Philippians:

I will continue to rejoice, for I know that through your prayers and God’s provision of the Spirit of Jesus Christ what has happened to me will turn out for my deliverance. I eagerly expect and hope that I will in no way be ashamed, but will have sufficient courage so that now as always Christ will be exalted in my body, whether by life or by death. (Phil 1:18-20)

Here, Paul speaks of the Holy Spirit as “the Spirit of Jesus Christ,” as well as the reason for his confident hope that no matter what happens, “Christ will be exalted in [his] body.” Moreover, as Paul tells the Galatians, “God sent the Spirit of his Son into our hearts” (Gal 4:6). Even Luke can equate the two in the book of Acts:

Paul and his companions traveled throughout the region of Phrygia and Galatia, having been kept by the Holy Spirit from preaching the word in the province of Asia. When they came to the border of Mysia, they tried to enter Bithynia, but the Spirit of Jesus would not allow them to. (Acts 16:6-7)

The “mystery,” then, is God’s divine plan that is no longer hidden or secret, the full good news of the gospel of Jesus Christ. The Colossians are in Christ, and Christ is in them — or as Paul puts it in his letter to the Romans, they are “united” with Christ (Rom 6:5). The Holy Spirit, the Spirit of Jesus himself, dwells in them. And because of this, they have “the hope of glory”; they know that the promise of joining Jesus in resurrection is dependable and true.

No one can completely explain what it means to have the Holy Spirit in us. Nor can anyone completely explain resurrection. Then again, I can’t explain everything about how my brain works either, and that’s not going to stop me from thinking. All these things are mysterious in that sense.

But God has made his plans known through Jesus, and our role is to live in the truth of what he has so graciously revealed.