The Tangled Tree

The other night I found myself watching a podcast on horizontal gene transfer. This was not devotional programming. It was the kind of show made for people who get a thrill out of biology and DNA and the deep machinery of living things. A physicist never stops being curious about how the world is put together. I settled in expecting an hour of good science. What I got was something closer to a sermon, though the hosts would have been astonished to hear me say so. Let me tell you what they said:

We are not who we thought we were, because we are composite creatures. The tree of life, they explained, is far more tangled than anyone first imagined. Genes do not merely descend vertically, parent to child, generation to generation. They also travel sideways—horizontally—leaping between organisms that were never supposed to share anything at all. There is, they said, a kind of infection at the heart of biology, one that transforms identity itself. And these transformations run in both directions: harmless to deadly, deadly back to harmless, an endless traffic across boundaries we thought were fixed.

They spoke of endosymbiosis—the strange cooperation of living things dwelling inside other living things. They spoke of living ghosts, ancient life-forms whose remnants still perform quiet, essential labor inside the cells of our own bodies. Whole genomes, they said, have gone sideways and been captured, folded into creatures they did not belong to. They described cases where dead bacteria appear able to transform living bacteria from one kind into another. Dead bacteria. Reaching across the grave to change the living.

Then, to my genuine surprise, one of them reached for the last page of the Bible. Revelation chapter twenty-two. The tree of life, yielding its fruit, for the healing of the nations. The scientists were taken with what they called the elastic version of life pictured there at the end of Scripture—a life that stretches out to cover everything. Biologist, they said, can use the sequences written in our cells to reach back and read the shape of the past. Do that carefully enough, and the universal tree of life begins to hold the secret of its own existence. History illuminating biology, and biology illuminating history.

I could not listen to a single one of those sentences without hearing Christ crucified underneath it. Every one of them. In real time, as fast as they could speak, my mind was translating.

Composite creatures. Of course we are. We are members of the body of Christ, no one of us is whole on our own, each of us has been grafted into something larger and stranger than ourselves.

The tangled tree. The scientists meant the tree of life, but I could not help thinking of the tree of the knowledge of good and evil—which is, God knows, more tangled than any of us first thought. And I thought of that other tree, the cross, planted at the center of history.

An infection that transforms identity. Here is the good news: the precious and holy infection humanity receives from Christ. It doesn’t just descend vertically, out of heaven, where the crucified One fills all things from above. It also transfers horizontally—passed hand to hand, neighbor to neighbor—as we treat one another with both the cruel indifference of Good Friday and the victorious, baffling love that God poured out on that very same day. The cross is an infection, and it does, indeed, change who we are.

And yes, the transformation runs both ways—deadly, then harmless, harmless, then deadly, back and forth, as though good and evil were braided together. That is precisely the scandal of the cross: the worst thing that ever happened and the best thing that ever happened, at the same hour, on the same hill.

Endosymbiosis. There is indeed Something living inside us—the new life, the new heart, the new mind of Christ, dwelling in cooperation with these mortal bodies of ours.

The tree of Revelation twenty-two. Yes. Christ is the tree, supplying his cruciform blessings to all creation, for the healing of every nation.

Elastic life. There is nothing more elastic than the gospel, which stretches to cover the whole of things without ever once thinning out.

Reading the past from the present. The interpretive key to every present moment, every future moment, and every moment long past is a single Friday afternoon. The cross holds the secret to its own existence. Understand the his-story of the crucified God, is understand all of life—not merely the biological kind.

Living ghosts. The Holy Spirit is the living Ghost who performs a thousand hidden functions inside these bodies of ours, ancient and life-giving and never idle.

And the dead bacteria that transform the living? I could hardly sit still. The resurrected Christ, in his eternally fatal condition—wounds still visible, death still upon him and yet swallowed up in victory—has annihilated the boundary between the living and the dead. That dead-and-ever-living body reaches across the grave to change us. He transforms sinners into saints while we yet remain sinners still, justified and sinful, both at the same time. Dead bacteria, transforming the living from one kind into another.

The whole program was about biology. Horizontal gene transfer, tangled trees, ghosts in the cell. The hosts were not preaching, and I do not want to put words in their mouths that they never meant to say.

But I am the physics pastor from the Santa Cruz Mountains, and I have long since given up trying not to hear Him. Christ crucified was in every sentence, sideways and horizontal, transferring himself into everything they touched. He always is. Once your cells have caught that holy infection, you begin to find him written into the deep grammar of the world—even in an hour of science on a weeknight, when you were only trying to learn something about DNA. He is the tree. He is the transfer. He is the life that goes sideways to reach us all. I will see you next Saturday evening. God bless you.