They were headed towards the central park. Their deliberate, feather-soft footsteps seemed to slow down time in the vicinity. Cars stopped to let them pass. Hundreds of hustlers on the sidewalks also paused to make way for the silent marchers.
I had been invited by Zen Master Thich Nhat Hanh to accompany him on a month-long trip through the U.S. to promote Buddhism.
For three months, I was fortunate to witness his influence on people from all walks of life, the respect and love that people of America had for a Vietnamese monk.
I remember his conference at the Boston Park Plaza, which was organized by Harvard University. 1,200 tickets, each worth $450, sold out within three days. Participants included businesspeople, politicians, prominent intellectuals... people at the very top. Among them was the family of the late U.S. President John F. Kennedy.
It seemed that Americans were struggling with an existential crisis. A therapist who participated in the conference later told me how he had treated thousands of his patients with depression. But he did not know how to escape from the fears and anxiety he himself harbored.
"I came here to listen to one of the world's most reputed Zen Masters speaking about mindfulness, so I can apply it in my job," he said.
"I want to help myself first."
There was a palpable silence in the hall, so silent that I could hear the people next to me breathing. The Venerable Thich Nhat Hanh stood on the podium and spoke. When he ended his speech, there was a standing ovation. He smiled at everyone and waved his hands. The crowd followed his gesture.
He walked down from the podium and asked people to walk mindfully.
There was another time when the Master spoke at Boston's largest cathedral. Over 4,000 seats quickly filled up. Those who were late had to sit on the floor, but they didn't seem to mind.
Below a statue of Jesus spreading his arms for humanity's salvation, Thich Nhat Hanh spoke to the thousands about Buddhism.
"We all have pain. Some are so scared of it they find other outlets to let it out, like movies, drugs, even their jobs. We don't know how to confront our pain and transform it.
"Therefore, the Buddha has taught us to recognize our own pain. If we can learn how to breathe, walk and eat mindfully, we would have the power to embrace our pain and let it go," he said.
It was surreal to see a Vietnamese monk standing in a cathedral to speak to more than 4,000 people about Buddhism.
Then there was the time that Thich Nhat Hanh met with then-World Bank Director Jim Yong Kim in Washington D.C.
Kim had read books by the Master and practiced mindfulness for several years. At their meeting, he said he wished to apply mindfulness to his work life as well. How can we stay calm amidst endless deadlines, he asked the Master.
"I have a clock. But there are no numbers on it, just 12 of the word 'now' to remind me that I'm alive. The desire to be at the top is a desire that's hard to be quantified. People can only choose one or the other: happiness or the top," the Master replied.
"To be happy is to be content. A stressful body cannot house a stress-free mind. Listening to your inner self is the key to solving most of your problems."
The Master then spoke of his childhood in Vietnam. When war was still raging back in the 1960s, he and his disciples took the risk of traveling to rural areas of central Vietnam to help the poor. He spoke of the self-immolation of monk Thich Quang Duc in Saigon in 1963 as a sign for humanity to start listening to the cries of their fellow men.
He also talked about his meeting with Martin Luther King Jr., about their discussion on the Vietnam War and ways to bring peace instead of war. But their dream was disrupted when King was assassinated in 1968.
At the headquarters of Google, Yahoo and other tech giants in the U.S., the Master taught the art of mindfulness to employees to help them become calmer, more creative. Many others attended his meditation courses, from teachers to senators. Many managed to rediscover the joy of life.
During a meditation course for Americans at the Magnolia Grove Monastery, the Master helped me take refuge in Buddhism and named me Tam Hieu Thuong.
"Hieu (to understand) and Thuong (to love) is the foundation of Buddhism. True love stems from true understanding. There is no love without understanding," he explained.
"We must live each day to understand others and to help others understand us. Love will wilt if we don't know how to nurture it with understanding."
Why do so many Americans and others around the world follow Thich Nhat Hanh's teachings? I believe it is because he didn't bring them the Buddhism that has to do with faith and prayers and rituals, but the Buddhism that happens with practice.
The Buddha isn't a deity but an enlightened person. Buddhism is a way to live with intrinsic rather than extrinsic motivations, without doctrines or revelations or any conflict with other spiritual traditions. In its true sense, Buddhism also isn't in conflict with science. With Thich Nhat Hanh's teachings, people grow in terms of knowledge and empathy, and it is that growth that brings them serenity.
For more than half a century, the Master has pioneered the "Applied Buddhism" movement in the West. His practice of mindfulness has proved to be deeply influential, not only because of its simplicity but also because of its effectiveness. The world has learned more about Vietnamese Buddhism thanks to Thich Nhat Hanh being a central figure.
His passing on Saturday was felt by millions across the globe. Most of them only knew him through his writings. But the legacy he has left behind will forever reverberate through his disciples and followers' way of life. As long as we remember how to cultivate tranquility from within ourselves, the Master will still walk with us, always.
I am deeply humbled to have been one of his students.
*Hoang Anh Suong is a journalist and an author. The opinions expressed are his own.