It had been a fruitful but exhausting day in Posadas, Argentina, a small city on the Argentina-Paraguay border. While Posadas is modern and well developed in many respects, its Jewish infrastructure is virtually nonexistent. In fact, the closest Jewish institution is the Chabad House in Buenos Aires, a twelve-hour drive away.

Like many places on earth, however, Posadas is home to a small number of Jews. We had spent all day getting to know these Jews—at their shops, homes and businesses, and random tourists as well. Most welcomed us warmly, and we were happy to be able to share some nuggets of Judaism with them.

Our appointments for the day—and our time in Posadas—complete, we stood in the street to hail a cab, anxious to get back to our hotel. We had to pack and sleep for a few hours before our early morning flight. We waited, five minutes quickly turning into fifteen, then twenty, then thirty. Occasionally a cab would drive by, already occupied.

“Let’s try waiting around the corner,” Shloimi suggested. We were walking past a small grocery when a couple emerged and immediately motioned us over. The husband introduced himself as Eduardo, an evangelical pastor, and started sharing his life story. “I am half Jewish,” he told us. “My mother was Jewish.”

“You are not half Jewish, Eduardo; you are as Jewish as Moses! You were born a Jew, and you are a Jew forever, no matter what—even if you are a pastor.”

We explained that as a Jew, he has the exclusive privilege of fulfilling G‑d’s commandments—the mitzvahs. “In fact, you can have a chance to do a mitzvah right now,” we continued, showing him our tefillin.

He eyed the tefillin, looking torn. “If my wife agrees, then I will put them on,” Eduardo decided.

We told her that when a Jew wears tefillin, it is a tangible expression of his bond with G‑d, our Creator. Before we could delve further, she said, “Go ahead. I think you should do it.”

So, 60-odd years since his bar mitzvah, Eduardo was finally able to put on tefillin. The magnitude of the moment was not lost on him, despite his present occupation. As we were winding the tefillin straps around his arm, the dam burst, and Eduardo started sobbing. We waited quietly until he was ready to talk.

“Please, do you have any Jewish books with you?” Eduardo implored. “I need to learn more about what it means to be a Jew.”

“Certainly. We’ll give you whatever we have.”

He had one last request. “Can I correspond with the two of you, and ask you my questions from time to time?”

Of course, we were more than happy to accommodate him. We exchanged contact information and promised to stay in touch. We were bidding Eduardo farewell when a vacant taxi materialized, exactly on schedule.