(UNDATED) My father and I were eating lunch at Marquette Manor, the retirement center in Indianapolis where he has lived since my mother’s death five years ago.

A friend walked up and put his hand on my father’s shoulder. The two began singing, my father on melody, his friend on harmony. They do this every time they see each other at lunch.

The day before, they sang “Down by the Old Mill Stream,” composed in 1908 to recall a lover’s first encounter with a 16-year-old “village queen” whose “hair has turned to silver.”

Today, as I again joined the melody, they sang a ballad much loved by U.S. soldiers crossing the ocean to World War I:

“There’s a long, long trail a-winding

Into the land of my dreams,

Where the nightingales are singing

And a white moon beams;

There’s a long, long night of waiting

Until my dreams all come true;

Till the day when I’ll be going down

That long, long trail with you.”

When we finished, residents applauded.

On our walk to lunch, my father and I had sung the ballad that dominated USO performances during the last two years of World War II: “I’ll be Home for Christmas.” Its final words — “if only in my dreams” — expressed a yearning that went beyond lonely soldiers on the front.

I grew up singing these songs. In those early years, I knew nothing of leaving home, the magic of young love, missing my homeland or seeing my father alone at age 93 after 60 years of marriage.

Yet what I did know, even as a child singing along while Dad played guitar, was the force of yearning — that tender and urgent longing for what is good and loving. Long before we lose what we have loved, we feel the power of yearning for that love, and we sense the risk of holding on to anything dear.

It’s not a morbid dread, but an awareness that life is fleeting and it takes great courage to love another person. It takes courage to care about a partner, a child, a parent, because as hymnist Isaac Watts said, “time like an ever-rolling stream bears all its sons away.”

Like soldiers huddling in trenches, we give each other courage by expressing our yearnings. We sing, we write, we draw, we pray. Songs don’t end wars, any more than singing at lunch can roll back the years to happier days. But our yearnings are what make us human.

Any animal can fight or steal. Humanity is at its best when we yearn for goodness and love, when we step outside our defenses and dare to imagine better. The darkness tries to drive us back inside by making us afraid of our own longings and by cheapening them. Our humanity draws us back to the stream where love can blossom.

Our yearnings are what connect us to God, as well. God isn’t to be known by a majestic throne, thunderous rage or finely tuned loathing. God is known in the risk of creating that which can betray its maker and surely will die.

Jesus told the disciples of his leaving, and invited them to love him anyway, because in loving and losing, they would know the fullness of God’s love.

In the songs of childhood, my father taught me to yearn for goodness and love. Now he is teaching me the courage to keep on yearning.

(Tom Ehrich is a writer, church consultant and Episcopal priest based in New York. He is the author of “Just Wondering, Jesus,” and the founder of the Church Wellness Project, http://www.churchwellness.com. His Web site is http://www.morningwalkmedia.com.)