A stranger came to help me out when I was stranded on the side of the road. He had a profound impact on my life.

• My partner and I were traveling back to university when our tire went flat.
• It was getting late and I hadn't learned how to take care of a flat tire.
• A stranger came alongside us to help us change the tire before dark and left without a word.

On the way back to university from a visit to see family, my partner and I found ourselves between a rock and a hard place. I was still pretty young, but, honestly, I should have known how to change a flat tire by that point in life. I started looking through the owner's manual for instructions as the sun began to set and a sense of unease started to settle over me.

We were still hours away from our destination and didn't have the money for a place to stay if I couldn't get the tire sorted out. I turned on the hazard lights and started to fumble around in the trunk for the spare and the jack. Just as I was about to pull the tools out, I looked up and saw an old pickup truck idling in front of our car. A man hopped out of the driver's side and made his way over to us.

I was completely caught off guard

Within moments, the man — without introduction or any small talk — asked for the tools and set to work. He talked through the entire process from setting the jack to loosening the bolts before removing the flat.

He was a lifesaver.

What he did in minutes would likely have taken me an hour (minimum). I helped him pull the old tire off, rolled the new one over, and helped finalize the process. The gentleman had me tighten some of the bolts on the spare just to get a sense of what it felt like to do it myself, and then checked my work before tightening the rest.

As quickly as he had arrived, he was gone

I was already feeling a very deep sense of gratitude toward our "roadside savior" and, as I put away the jack, started planning out my thank-you speech. My partner watched nearby as I heaved the flat into the trunk and finally slammed the lid closed.

As I opened my mouth to begin gushing out thanks, my partner and I realized simultaneously that the man was gone — truck and all. We didn't hear him get in, close the door, or drive away down the service road. It seemed impossible that he could have left as quickly as he did, and even less likely that neither of us wouldn't have noticed or heard his departure.

We stood in awe of the unlikely moment we found ourselves in and looked at each other, speechless. This wasn't characteristic of the US we were taught to believe in, where people were robbed or harmed on the side of the road in situations such as these. Nevertheless, we were able to get in our car and make it to the nearest town just in time to find a new tire and be on our way back to school.

The care from a stranger caused me to reflect

After the fact, I spent considerable time reflecting on what that episode meant for the way I see others. I look back now and see how small moments of generosity have helped form my worldview today.

At the time, I was apprehensive and unsure of how to accept the help I received from a stranger, and, if I'm honest, I experienced some fear when he pulled up out of the blue. However, my initial judgment of the situation proved incorrect in the kindness of our unknown friend's gesture. I had to take some time to think about my own response to people whom I might encounter who could be going through a similar struggle.

Single moments can deeply impact others

I know I will never get to thank our "angel in a pickup truck," but I hope some of my own opportunities to help in times of need have been the thank-you I would have given him.

This moment, and others like it, have caused me to try to adopt a posture of what some call "radical hospitality". We are all affected by an accumulation of moments that we string together to form who we are as people, so the way we respond to others in any given situation can alter key aspects of someone's life or worldview. It pays off to give generously when the opportunity is there. It is also just as generous to receive from others with a deep sense of gratitude.

The stranger who helped me with my flat may or may not have thought about what effect he had on me, but his impact will last a lifetime.