Sermon — Christmas Eve, 2021

The Rev. Greg Johnston

“The light shines in the darkness, and the darkness did not overcome it.” (John 1:5)

I had a parishioner once who was a professor at MIT. He was an astrophysicist, so one Lent we invited him to give a talk during our Adult Forum on the topic of “Light.” He began by showing us a picture of a telescope he’d worked on as a grad student, a massive instrument housed in a 130-foot-tall concrete dome. In that dome there was a narrow slot through which light could enter, bounce off the 200-inch mirror, and be detected by an array of sensors, one of which he’d helped build.

So he showed us the picture of this huge dome, with himself standing on the floor for scale, and then he said: Consider this. Two and a half billion years ago, the super-luminous core of a galaxy two and half billion light years away emitted a photon, a single particle of light. The photon sped forward in more or less a straight line as the galaxies shifted and the universe expanded, and by the end of the first billion years, simple multi-celled organisms had begun to live on earth. Another billion years passed, and by the time it was only about 500 million light years away, plants and mollusks were beginning to thrive. Over the next quarter of a billion years the dinosaurs rose, and fell, and the light flew on. As the photon began the final leg of its journey, the face of the earth began to be transformed in what seemed like the blink of an eye. A new kind of ape stood upright and began to spread around the world. They discovered fire and wheels and agriculture; they built cities, and temples, and eventually telescopes. And in the kind of Hail-Mary connection a quarterback could only dream of, as the universe expanded and the sun moved within our galaxy, as the earth revolved around the sun and rotated on its own axis, the photon arrived at precisely the right place at precisely the right time to slip through the slot in the dome of the telescope, where, in the blink of an eye, it missed the edge of the mirror by six inches and crashed into the floor, never to be seen by a human eye.

(The light shines in the darkness, and… sometimes the darkness overcomes it.)

On these shortest days of the year, when we can start a service at four o’clock and know that it will end in deep darkness, we gather to celebrate a festival of light. Like people do in the midwinter all around the world, we light candles and warm ourselves by the fire and try to figure out how to pronounce the Danish word hygge. (Hee-geh? Hyuu-geh?)

These holiday festivals are not just about the light and the warmth of our candles and fires driving away the gloom and cold of a dark night. They’re about the warmth and love of a community dispelling the loneliness and fear of dark times. And when we, as Christians, gather to celebrate this holy night, it’s not simply a celebration of light, in general. We gather to celebrate the birth of “the true Light, which enlightens everyone.”

We’re using to telling the Christmas story as the story of the birth of a child, not the story of the lighting of a lamp. We’re used to hearing the classic Christmas-pageant tale: the census and the journey, the parents and the donkey, the shepherds and the angels and the babe wrapped in swaddling clothes, and lying in the manger, because there was no place for them in the inn.

Yet in a way, it’s this other story, this story from the opening words of the Gospel of John, that matters more for us today. After the census has been taken and the Holy Family returns home, after the shepherds’ shift ends and the angels’ echo fades, after the babe outgrows the swaddling clothes and moves from manger to crib to toddler bed, two thousand years and more after the events of that first Christmas night, “the light shines in the darkness.” And the darkness has not overcome it.

If you were totally depressed by the story of the photon’s two-billion-year journey, you can thank God for the law of conservation of energy, which suggests in part that light can never be wasted, only changed. The energy of that single photon, at the end of its voyage across the universe, could not disappear. Perhaps it was absorbed in the concrete, its energy transformed into heat and radiated back into the air. Perhaps it was reflected, bouncing off the floor and shining in an astrophysicist’s eye, or pinballing its way back out into the universe. But energy, while it can be transformed, can never disappear.

            The light shines in the darkness, and its legacy can never be erased. The light of Christ shines even now on us, and it cannot go to waste. Some of it we see, and we call it a spiritual experience, a moment of awe and wonder and grace. Some of it we absorb unnoticed, and it helps keep our hearts warm with love.

And most of it we reflect, as the light of Christ bounces off us and is scattered into the world. God loves us, and we love one another in turn; God’s light shines on us, and we illuminate one another’s lives. Like John we bear witness to the light. In word and in deed we “testify to the light’s” presence in the world.

In fact, we don’t simply “testify to the light.” We are “enlightened,” by the “true light, which enlightens everyone.” (John 1:9) We’re not “enlightened” like a practiced meditator is “enlightened” or like an open-minded person is “enlightened.” It’s a transitive verb; Christ en-lightens us. He fills us with light, transforms us into light, makes us shine with our own radiance. We’re not mere mirrors, reflecting the light of Christ; we’re candles, lit on fire by one central flame, sharing our light and our warmth with one another as the fire grows and spreads, and each one of us becomes a new source of light in the world.

You are light, shining in a dark world. You have been “given power,” John writes, “to become children of God,” and you blaze with all the light of the holy child of God. For a billion years before your birth God waited with eager anticipation, wondering what new warmth your light would bring to the world, and now here you are, shining.

It can be hard to see the light of Christ in one another. It can especially hard, sometimes, to see it in ourselves. It can be so hard, in fact, to see the divine light shining in every human being that God had to come down and show us Godself. God had to hang a comet in the sky, and plant dreams in Magis’ minds, and summon shepherds keeping watch in their fields with a heavenly chorus, just to show them one simple truth: the light that you seek is not far up in the heavens, where the Magi gazed and the angels sang. It’s here, now, among you, in this most extraordinary ordinary thing: a helpless infant and his two parents, exhausted, uncertain, and full of love. Which is a real 2021 kind of mood.

There’s a happy ending to the story of the little photon that couldn’t, and it’s almost as mind-bending as the beginning. Because the quasar from which this light’s unbelievable journey began didn’t just emit one photon that happened to barely miss a telescope, never to be seen. It was so bright for so long that it gave off so much light in every imaginable direction that enough of it did in fact arrive at this telescope on this planet to be seen, and measured, and to contribute to yet another leap forward in our understanding of the cosmos. The universe is full of light. Only a fraction of it will ever be observed, but none of it will ever go to waste.

A new light was kindled in that manger in that stable all those years ago, wrapped in swaddling clothes, and we are awash in its light. From it, a new candle was lit at your birth, however many years ago, and it still burns now, however undetected it may be. Only a fraction of its light will ever be observed, but none of it will ever go to waste.

So let your light shine, whatever the world may say. Tend that flame within you, however much it may seem to have dimmed. Search for that light in one another, however difficult that can be, and turn your mirrors to reflect its glory.

We will never know what one particle of God’s light will do as it bounces between us. We will never know what one kind word or one small gesture has meant, as the light passes from person to person around the world. But we do know that “the light shines in the darkness; and the darkness did not,” and the darkness will not, and the darkness cannot overcome it, because darkness is nothing but the absence of light; and the light will never go to waste, even if it takes two billion years and more to be observed.