New Zealand Prime Minister Jacinda Ardern praised the bravery and courage by worshippers as a lone gunman massacred their friends and family.
She says the nation stood with its grieving Muslim community in this "darkest of days".
Hati Mohemmed Daoud Nabi, 71, opened the door to the Al-Noor mosque. Ardern said he "uttered the words 'Hello brother, welcome'. His final words".
"Of course he had no idea of the hate that sat behind the door, but his welcome tells us so much – that he was a member of a faith that welcomed all its members, that showed openness, and care," she said.
"The families of the fallen will have justice," said Ardern, adding she would never mention the alleged gunman's name.
Wife of British academic jailed in the UAE - "We are waiting"