Why would an oncologist care about the biblical Christmas story?

Early in medical school, as a religious 20-something, I found great comfort in molecular biology. Like Francis Collins, director of the human genome project, I intuited in DNA “the language of God.”

The processes by which cells replicate and utilize DNA bespeak elegance, efficiency, beauty and divinity. Even the most hardened skeptic can hardly help but stare in wonder.

And yet, no sooner had we finished learning about human physiology than we began exploring pathophysiology.

Having spent those first months learning the wonder of the body working aright, we spent the next months learning all the ways things could go wrong.

Of all the diseases we learned about, perhaps none is so philosophically and theologically dispiriting as cancer. After all, cancer involves no foreign invading bacteria. Rather, it arises precisely because of the very godly processes that so struck Dr. Collins — and that had spoken so deeply to my soul.

My patients almost always want to know why they developed their cancer. Was it something they ate? Something they did? Something their parents passed on? But in most cases the origin of cancer is built into the very miracle that allows all life to function and grow.

Cancer, as Siddartha Mukerhjee has observed, is our own biology turned against us.

And it’s not as if the consequences are in any way abstract, subtle or theoretical.

Cancer cells devastate my patients every day: infiltrating lung, liver and brain; filling the belly with unending fluid; trapping the lungs inside growing pools; strangling the bowels; disordering the brain; robbing mobility and even the ability to talk; decimating family; widowing young mothers; attacking the young and the old, the vigorous and the ill.

What’s more, the native origin of cancer renders our treatment horrendous.

Because cancer cells are our own cells gone rogue, when we create chemotherapy drugs, we must accept that we will poison our own cells, as well

In consideration of all this, it seems little wonder that Bertrand Russell famously concluded we are nothing but “random collocations of atoms.”

So in the midst of all of this — what use is the Christmas story?

In the face of evil quite literally written into our own genetic code, what room is there for rejoicing and what can it possibly have to do with a baby in a manger born more than 20 centuries ago? Certainly the notion that such a meager setting housed anything more than just a baby should strike a hardened oncologist as the most offensive kind of folly.

Given the millennia of suffering, cruelty and sorrow — and cancer — that have flowed since the birth of Jesus, what can it really matter if angels sang above a shepherd’s plain those many years ago?

But that is the special calling of religion and the unique province of belief — to stare into the yawning chasm of despair and absurdity and nonetheless proclaim I believe.

To see in that manger salvation come down from heaven, to believe that an impoverished refugee would transcend sin and death to transform women and men and eventually bring justice and peace to Earth is the height of folly — unless it is true.

Such belief requires choosing because the commitment to the religious life is, and always will be, that: a choice.

Caring for meaningless organisms that happen to be riddled with cancer cells would be, after all, little more than a testament to the randomness of those atomic collocations.

Yet, paradoxically, to care for people who have cancer — and seeing their bone-deep kindness, grace, forgiveness, wonder and love — is to recognize that beyond the cells and DNA lies a deeper truth: We cannot be reduced only to cells and atoms. Life means something more.

Dr. Tyler Johnson is a clinical assistant professor at Stanford School of Medicine and inpatient oncology service director at Stanford Hospital.