An estimated 300,000 Buddhists descended on central Seoul on Saturday evening local time, packing the blocks around the Gyeongbokgung -- the main royal palace -- to pray for peace and reunification with the North.
The event was staged to mark the 70th anniversary of Korean independence, and it brought together Buddhist leaders from around the world.
In a rare interview with CNN, the spiritual leader of the Jogye order of Korean Buddhism -- the country's largest sect -- the Supreme Patriarch Jinje, said it was also the anniversary of Korea's separation.
"The separation has been causing pain for the people," he said.
"To solve this problem, we are focusing on peace for the Koreas during this Buddhism meditation assembly. The purpose of this meditation is to bring peace to all the people -- people of the whole world."
South Koreans on the whole are not particularly religious. But for the approximately 20% of South Koreans who practice Buddhism -- according to a 2014 study by Gallup Korea -- Master Jinje is a key spiritual figure.
Hwang Yeon-gyeong traveled from Seongnam on the outskirts of Seoul to join in the event. "With the mercy of Buddha, we should come together as the same people and I hope we can realize peaceful reunification," she said.
This is a goal that has eluded politicians and diplomats for decades.
U.S. Secretary of State John Kerry is in Seoul to discuss security on the peninsula. With North and South Korea technically still at war, recent reports out of Pyongyang have done little to ease tensions and anxiety south of the demilitarized zone that separates the two neighbors.
North Korean state media hailed the successful launch of a ballistic missile from a submarine
just over a week ago -- an event Kim Jong Un called a "miraculous achievement." South Korean defense officials estimate the North could have a fully operational submarine armed with ballistic missiles in four to five years -- though many analysts are skeptical about this. Then, there were reports from South Korea's spy agency that Kim had his defense minister purged and executed
-- though officials in Seoul cannot confirm this.
We asked Master Jinje what role Buddhism could play in reunification efforts, especially since the only religion in North Korea is the Kim dynasty itself.
"In North Korea, there are 500 years of Buddhism rooted in every person's heart," he said. "We are carrying the spirit of mutual help and I believe there will opportunities for people to open up their hearts in the future. That is why we should not neglect, but rather help each other."
He said leaders from the North and South met recently in China and that Buddhists had been working to restore temples in the North. Korean Buddhists also promised more humanitarian aid programs.
But the Supreme Patriarch would not expand on whether Buddhists planned to play a more active role -- perhaps take a leaf out of Pope Francis' book, after the Vatican's contribution to bettering relations between Cuba and the United states; or look to the pivotal role German church leaders played during that country's reunification.
But his approach is more spiritual.
"When we practice our daily asceticism," he said. "We make all conflicts in our heart disappear.
"By instilling these ideas in all people and the people of the two Koreas, I'm confident that all envy and conflict will disappear and that the reunification of the two Koreas will be quickly realized."
For the Buddhist leader, peace begins from within.