I was eighteen. It was just after Passover. I was one of a group of six thousand Jewish teenagers and two thousand Holocaust survivors on a trip back in time.

This trip, the March of the Living, took the group to the concentration camps, where our mourning was swallowed by the cry of the wind whiffing around the now stilled smokestacks of Auschwitz, Birkenau, and Majdanek. From the camps, we traveled to Israel, seeking refuge from the pain in a land all our own, as had millions of others before us. The difference was that we had made it, and we could hold Israel's dry earth between our fingers, where so many had died trying just to set foot on the sacred soil.

A busy teenager, I had not elected to go on the March. Only an unforeseen turn of events, involving a complete scholarship for the trip, found me sharing this intimate journey with six thousand strangers.

My going on the March was one of the many instances of G‑d’s hand at the wheel of my life, and perhaps the first time I was aware of His directions. We travelers were immersed in an era and in a place that, paradoxically, did and did not belong to us; thrust into the tumult of the trip, we had no choice.

The bus entered the town of Tikocyn, a small hamlet about an hour away from Cracow, Poland. I stared goggle-eyed from my seat on the bus. The bus squeezed and jostled its way down a narrow, rutted dirt path lined with ramshackle one-story houses, each with two windows, a door and a chimney, like a first-grader's drawing of home.

We drove past a toothless woman bent feeding the chickens in her yard. I watched her pursed lips and her wobbling chin as she clucked to the chickens, tossing pale golden grains from their cache in her flowered apron. As we passed her, she made no acknowledgement of our presence. I felt invisible.

Farther down the road two old men stood talking. One wore a hat with earflaps, the other, a bloody apron. I was reminded of Lazar Wolf, the butcher, from Fiddler on the Roof. They laughed; their bellies shook. They went about their lives as if buses full of Jewish teenagers and Holocaust survivors passed by every day. We drove on.

The bus drove by a group of schoolchildren. Unlike the old woman and the men in their stepped-out-of-time costumes, these children wore jeans, colored sweatshirts, sneakers—they looked like 'real kids.' My eyes met those of the little boy nearest the bus. I smiled at him, waving.

The little boy raised his arm and pointed. "Zydi!" Jews! "Zydi! Zydi!"

In seconds, all the children followed the little boy. "Zydi! Zydi!" They pointed and laughed and made horrible faces. I felt stung and freezing cold, as though I had dunked in a bath of ice water. No amount of warm clothes could fix it. What were we doing here?

The bus pulled up in front of a grassy clearing. I was shivering, but allowed myself to be herded with the rest of the group into a building about the size of a modern-day classroom.

It smelled like earth and paint. The building—the shul of Tikocyn, the rabbi on our bus explained—had once been a striking structure, a landmark of beauty in this bleak place. When the Nazis, may their names be erased, arrived in Tikocyn, they quickly and efficiently disposed of the town's Jews in a mass grave in the nearby woods. The shul in which we now stood only remained because the Nazis had used it as a stable. Most of the walls had been smashed; the lines of Psalms that had once been painted on every surface remained in bits and pieces where the plaster had not been destroyed.

Within the walls of the shul, I heard echoes and I could almost see people, smiles from the past, clasping each other's arms, dancing. The chill inside me went deeper and I wanted to cry. What was left?

"Ah," said the rabbi heading our bus. We were waiting for the caretaker of the shul. "Here he is."

A wizened old man shuffled through the doorway. Watching him slowly walk towards us, seeing the deadened look in his eyes, we knew where he had been. He looked up and saw us—two hundred strong, only a fraction of the six thousand—and clapped his hands together.

"Yism'chu, v'mal'chu's'cho, shoymrei, shoymrei, shoymrei Shabbos, v'koyreh oyneg Shabbos…" he sang. His thin voice filled the shul. His eyes lost their haunted, hollow look; joy shone from his face as he gazed at us.

I did not know the words or the tune. But I knew that I wanted him to keep singing.

Someone in our group brought his hands together, clapping in time to the old man's song. Others joined in with the words. Still more of us followed the tune as best we could, making up the words as we went along. I linked arms with the girls beside me, letting the old man's song fill the cold place brought on by the jeering children minutes before.

Then I knew why we had come.

At Passover, we celebrate our redemption from Egypt, leaving in haste—thus the matzah—but leaving on our terms. We were not allowed to leave Tikocyn, Auschwitz, Majdanek.

Unless, now, we fight back.

The Torah says that a Jew must consider himself as if he personally had come out of Egypt. What kind of Egypt? An Egypt, perhaps, where the Pharaoh wore a swastika. An Egypt of a generation whose story is only told through the old man's song, and through those given the chance to hear it. Through the song, we fight back.

In the old man's song, though I did not understand it that day, were the silenced voices of our brethren and the voices of children waiting to come down to this world. In the old man's song I heard G‑d's promise to us that we, the Jews, would be as numerous as the stars, and a plea as ringing and strong as a brass bell that we, the young ones, must help to fulfill that promise. It became our task, as the old man's voice reached the crumbling rafters of the shul in Tikocyn, to embrace and to keep G‑d's Torah in any way we could.

In the old man's song I heard not the anguish of the past but the surety of a gleaming, vibrant future. That day, I vowed to fight back—and to listen to the old man's song.