It was 26 May 2017 on the Portland MAX light rail service when a white supremacist named Jeremy Christian began threatening two teenage girls; one of the girls was black, the other in hijab. Three other men, all strangers on the same train, stood up to Christian, defending and ultimately saving the girls. Christian attacked the three men with a knife, killing 53-year-old Ricky John Best and 23-year-old Taliesin Myrddin Namkai-Meche and injuring Micah David-Cole Fletcher.

As Taliesin was bleeding, another passenger, a woman named Rachel Macy, knelt with him, comforting him and staunching his wounds. Taliesin knew he was dying. “Tell everyone on this train I love them”, he said to Macy in his final moments.

These beautiful words stopped me in my tracks when I first heard them. They gave me a directive, a way of being. At my best moments, this stranger’s last words guided where I looked, how I acted, and what I chose to do with my time.

Taliesin Myrddin Namkai-Meche’s mother describes her son’s last words as “the most important thing in the whole process”. Taliesin’s father says that when he heard what his son said, “It was literally a saving grace for me.” They were a saving grace for me, too: they changed my life.

Loving everyone on the train meant I could love people I didn’t yet know. What Taliesin said felt instinctually correct to me yet was simultaneously baffling. It often seems there are impossibly huge chasms between me and others, so how could I love them?

The heroism of the men on the train spurred many to react in all sorts of ways. A crowdfunding account called “Muslims Unite for Portland Heroes” raised more than $600,000. Many people, myself included, took Taliesin’s final message into their hearts. Strangers wrote songs and made videos and artworks about his actions and words.

The public reaction to the men who saved the girls on the train, and Taliesin’s words, helped his family through the trauma of his death. I talked with his parents last month. “I think if there weren’t such a major up-swell of compassion and energy that came out of that, I would have had a lot harder time with the whole thing,” his father, Christopher DuPraw, said.

“It was quite miraculous just how it expanded. That energy of ‘tell everyone on this train I love them’ completely shot around the world and on some level made it OK.” He laughed a little as he said that last part, still seeming to marvel at the fact.

There is much to marvel at in the story of Taliesin’s life and his death. He was young, just 23, and according to his friends and family members he was a funny, energetic, compassionate person with a drive for adventure and a deep understanding of the need for social justice. Women adored him and vice versa; he loved to gamble; his friends stayed his friends for ever.

Taliesin’s mother, Asha Deliverance, said, “He really fully believed that his life could help make change happen. And he had enough fire behind him to really believe that. He was not a lost soul at all; he was a soul with purpose.”

The last time she saw Taliesin was on Mother’s Day, and she asked him why he didn’t drive to work, offering to pay for a parking garage so that he didn’t have to take the train. He told her he just preferred public transport. Asha wonders now if that was her mother’s intuition warning her to get him off the train. At the same time, she is confident that Taliesin was on a path, and was not to be diverted. He was intentional about the importance of love, and when he defended the girls against Islamophobia and racism on the train, he meant it. She knew he was living his beliefs when he was killed.

“He chose to do that. That became very apparent within a few days, that this was a massive statement he was making. I never questioned or doubted his choices.”

Christopher sees his son’s last words as having meaning that will carry into the future. “I feel like this is an ongoing saga. His message was a unifying message, but so much of what we are dealing with today is so divisive, from Trump to Covid, and it makes it so hard, just so difficult for people to get back to the unified consciousness.”

He sounds sad, just for a moment, but I hear him brightening, and he adds, “But there is always that reminder somewhere if people look for it. And hopefully, they’ll keep looking for it.”

I find that reminder in Taliesin’s words whenever I think of them. For Asha, the words that have come to mean so much to so many people still remind her mostly of one person: her son. “Of course, I miss him sometimes, but also I don’t miss him because he often just shows up the minute I think of him – and I feel the love.”

• Maeve Higgins is a Guardian US columnist and the author of the book Tell Everyone on This Train I Love Them