The father of Sydney siege victim Tori Johnson said he wants to make sure his son's death is the "beginning of something new in this world".
Acclaimed artist Ken Johnson said the tens of thousands of flowers left as tributes at a makeshift memorial in Martin Place were "overwhelming, promising and exciting".
"Keep it rolling, get rid of cars and put flowers in the street, pave it all the way down to Central, that's what I would like, though I know that's impossible."
Mr Johnson organised to attend the memorial with Jewish, Muslim, Hindu and Christian religious leaders on Thursday evening.
He was also accompanied by friends and family members, including his daughter Radha, who placed flowers on the memorial, and former wife Rowena.
"I want to show solidarity. I want to demonstrate that there can be peace in the world. My son has paved the way for that and I want to make sure I continue it," Mr Johnson said.
His son Tori, 34, was the manager of the Lindt Chocolate Café and died in hospital after being shot during the siege on Monday night.
"I have just one thing to say, it's my son, his love is immense but his bravery is immeasurate."
Mr Johnson spent nearly an hour making his way around the shrine, speaking to members of the public leaving tributes and the religious leaders.
He said his son, who had run the cafe for two years, would be shocked by the incredible outpouring of emotion evident at the memorial.
"He wouldn't want all this. He is a simple boy who just liked going to work and going home like everyone else."
"I want to meet the person who put the first [flower] down."
Mr Johnson said he hoped to get in contact with the family of Sydney barrister Katrina Dawson, who was the other hostage who died in the siege.
The religious leaders who accompanied Mr Johnson around the memorial were Rabbis Levi Wolff and Zalmen Kastel, Hindu priest Pandit Ramachandra, Reverend Bill Crews and Sheikh Wesam Charkawi.
Mr Johnson, who had visited the memorial the previous day, had reached out to each of them to return with him to conduct shanti, or peace, chants.
"We have people from all faiths coming together to show that we are a very strong united people and a strong country. A small, little bit of light distils a tremendous amount of darkness," Rabbi Wolff said.
Posing with the religious leaders for a photograph, Mr Johnson said: "peace on earth".
He said that his family was "strong" and "doing alright".