The Reverend Ken Newell admitted to having paraded past the church in his earlier years, which has a controversial recent history.
Dr Newell said that this played a key part in his vision for reconciliation.
“I came past it on my first Twelfth of July in 1961 when I was marching and the bands began to ratchet up the volume,” he said.
“I looked in and I felt the music was somehow targeting the people in there and my conscience didn’t feel good about that.
“It made me feel that there was something wrong that needed to be put right and that we need to learn respect for each other’s places of worship.”
Dr Newell shared his story as part of the city’s Four Corners Festival, detailing his journey from chaplain to peace activist.
Fr Martin Magill, one of the organisers of the festival, said that the setting was chosen for a specific reason.
“I’m very conscious that this church has been in the media and more often than not, in unfortunate situations,” he said.
“Tonight we have a peacemaker coming here and I think his presence has been very welcome and presents this whole area in a very positive light.”
Dr Newell is the first Protestant to ever have been given a peace-making prize by Catholic peace movement Pax Christi International.
His passion for peace and a changed city remains as strong as ever.