IF YOU WATCH crime dramas and murder mysteries on TV, you’ve seen the same plot played out again and again. The character at the center of the story — often a woman — knows that someone has been murdered, and may even know who did it. She goes to the police, but they don’t believe her because she has no solid evidence of a crime. Someone may even invoke the legal principle of corpus delicti, saying that you can’t charge someone for the crime of murder if you can’t produce the body. So the search is on. She has to find someone who will take the case, help her solve the mystery, and vindicate her in the end.

Sound familiar? It makes for good drama. One problem, though: that’s not what corpus delicti means. The word “corpus” doesn’t refer to the body of the alleged victim, it refers to the body of evidence needed to bring a charge. It’s harder, of course, to make the case without being able to produce the victim — but not impossible. An actual body is not required.

The same cannot be said, however, of the gospel. As the apostle John tells his readers, the gospel requires a body.

HAVING MENTIONED THE Holy Spirit at the end of chapter 3, John turns immediately to the matter of other spirits at work in the world. He warns his readers that false prophets are everywhere, speaking as if they have God’s truth, but knowingly or unknowingly spreading lies. More specifically in John’s community, that meant that people had tried to push their aberrant ideas about Jesus onto others, causing conflict and confusion. John therefore gives his readers a litmus test for the truth:

This is how you can recognize the Spirit of God: Every spirit that acknowledges that Jesus Christ has come in the flesh is from God, but every spirit that does not acknowledge Jesus is not from God. This is the spirit of the antichrist, which you have heard is coming and even now is already in the world. (1 John 4:2-3, NIV)

As I’ve said before, it’s impossible for us to know with certainty what these false prophets had been teaching. But these verses suggest that it had something to do with the bodily existence of Jesus. While the false prophets may have agreed that Jesus had come, they denied that he had come “in the flesh.”

That might sound puzzling to us, but was probably less so to people of John’s time. Various versions of what’s known as Gnosticism were already at work in the culture at large (we might think similarly of the way so-called “New Age” ideas have permeated our own world). The term Gnosticism stems from the Greek word gnosis, which means knowledge. Gnostics generally emphasized having personal, spiritual knowledge or insight which was taken as a spark of the divine in an individual — which could authorize going rogue and rebelling against received religious traditions. Moreover, material existence was seen as the creation of a lesser god and therefore denigrated in comparison to the spiritual.

Think about it for a moment. If someone in John’s day already had Gnostic leanings, how would they hear the gospel? For example, how would they understand the gift of the Holy Spirit? Probably as that spark of the divine — and in a way that would have encouraged people to be more self-centered, not less. More importantly, what would they have made of the idea that Jesus was God in the flesh? The divine, become physical? With an actual — gasp! — body? Heaven forbid! Imagine further how such folks in John’s community would have been completely convinced that they were right and everyone else was wrong and in need of conversion. That’s one way to reconstruct the conflict that divided the community.

No, John insists. The true gospel of Jesus Christ requires more than a body of ideas or spiritual insights. It requires a physical, flesh-and-blood body.

We may take that belief for granted, but we shouldn’t. There are multiple consequences to denying the Incarnation. If Jesus did not have a physical body like ours, then he was not a true example of how one can live righteously in the face of sin, suffering, and temptation. God does not simply impose impossible requirements on his people in a way that ignores their brokenness. As the writer of Hebrews says, “For we do not have a high priest who is unable to empathize with our weaknesses, but have one who has been tempted in every way, just as we are — yet he did not sin” (Heb 4:15).

If Jesus did not have a physical body like ours, he could not stand in as our substitute on the cross to make atonement and reconcile us to the Father. Jesus constantly referred to himself as “the Son of Man,” which many interpret to mean something like the “quintessential human.” We as humans are inescapably physical, and this was part of God’s good creation. If Jesus did not come in the flesh, then he was not human.

If Jesus did not have a physical body like ours, then his resurrection cannot be the sign of our own future hope. Our eternal destiny is not some esoteric disembodied existence to be absorbed back into the divine. If by God’s design we were created to inhabit a physical world, then our proper destiny is to live in such a world that has been redeemed and cleansed from sin and death. As the apostle Paul insists, we will one day have resurrection bodies, and the guarantee of this is Jesus’ own bodily resurrection.

If Jesus did not have a physical body like ours, then he was not the embodiment of the love of the Father, a demonstration of what it means to live a life of love toward our fellow embodied humans. In fact, this point seems crucial to John’s letter. As the saying goes, it’s possible for people to be so “spiritual” that they’re no earthly good. That’s exactly the opposite of how John wants his readers to be. The children of God must love others in concrete ways; that’s how they demonstrate the family resemblance.

I’ll say it again: the gospel of Jesus Christ cannot be simply a body of beliefs or insights, such that once we have them, we no longer need the historical Jesus. The gospel requires a body. It requires the Incarnation. And those who know this will also realize that we have been given the Holy Spirit to help us embody the Father’s love as well.