It was a cold night in late December fifteen years ago. I was on the interstate near Philadelphia when the snow began to fall. I was driving home to New Jersey after a series of interviews for medical residency programs. I was tired but eager to get home to attend a performance of The Nutcracker, an annual family tradition.

Traffic was at a standstill. Looking at the dashboard, I noticed the temperature gauge climbing. Soon, the engine was smoking. “Oh no,” I thought, “I am alone, in a strange city, in a rough area, dressed in a suit and pumps.” I had five dollars, no AAA card, and no phone. I eased the car to the side of the road. I had two options: Hope that someone would stop to help, or hoof it to the next exit.

I popped the hood, got out of the car, and looked into the engine. It was an incomprehensible jumble of steaming metal and hoses. A man stopped and asked if I needed help. Peering under the hood, he reached for the radiator hose and pointed to fluid leaking from a crack. He offered to add some water to the radiator so that I could drive the car to a service station. I accepted his offer. He retrieved a thermos from his truck and poured in some water. Then he closed the hood and wished me luck.

I drove along the shoulder and prayed Hail Marys until I reached the next exit. The engine began to smoke again, but I made it to a convenience store. I sat in the car, afraid. This wasn’t a good neighborhood, and I noticed a slightly disheveled man watching me. I finally got out of the car and walked past him into the store.

I bought a roll of duct tape and some radiator fluid. I paid with a credit card my father had given me for emergencies. The disheveled man continued to watch me. Feigning confidence, I opened the hood and tried to locate the hose. As I did so, the man approached. He asked if he could take a look. He was a truck driver, he explained, home for Christmas. He’d just missed his bus.

He reached into the engine and manipulated the hose with the dexterity of a surgeon. Using his pocket knife, he cut some tape, wrapped the hose, and refilled the radiator. “It’s not gonna work,” he said. “The tape won’t hold for more than a few blocks. You certainly don’t want to break down around here after dark.”

He knew of an auto parts store a few blocks away. If we drove there, he could pick out a hose and install it. I hesitated, thinking of all the reasons I shouldn’t let this guy into my car. But in desperation, I agreed. I told him I had only five dollars and couldn’t pay him. He said he didn’t expect anything in return.

Climbing into the passenger seat, he set the pocket knife on the console. My heart skipped. We drove down several back streets, lined with warehouses. I tried to talk. I told him I was a medical student. He told me his name, Ray, and said he was on his way to visit his girlfriend in an alcohol rehabilitation program. “Alcoholism ruins lives,” he said. We made several more turns, and I had no idea where we were. Finally, the store came into view. We pulled into the lot, steam billowing from the car.

They had the right hose-the only one left in stock-and I used my father’s card again. Outside, Ray replaced the hose in a matter of minutes. I told him he worked like a surgeon. He said that I seemed down-to-earth, someone patients could talk with easily, and suggested I try to keep that trait. When he had finished, he shook my hand and started to walk away. What could I do? I offered him a ride.

Since it was too late to go to the rehabilitation hospital, he asked if I’d drive him home. We set out toward South Philadelphia, miles away. Finally, in a neighborhood of small row houses in need of repair, he asked me to stop the car and let him out. I thanked him. “You’ll get to that ballet with time to spare,” he said. “Take care of yourself, and Merry Christmas! Remember to pass along the kindness to someone else.”

I cried tears of relief and fatigue most of the way home and through the ballet. I’ve never seen Ray again but I remember him often, usually at this time of year, or when someone whom I might otherwise avoid turns up in my exam room. Ray also motivates me, years after that December night, to volunteer at a Franciscan clinic for the uninsured and homeless. And sometimes when I see a rig on the highway, I look to see if he might be behind the wheel.