Haji-Daoud Nabi died after being hit with three bullets while trying to save others.
A Givealittle page to raise money for his funeral arrangements said he was "a true hero" for his "selfless act".
And his sacrifice was in character, the Telegraph reported.
Omar Nabi, one of four sons, said his father made a habit of going to the airport to greet refugees and help them begin their new lives in Christchurch.
"Whether you're from Palestine, Iraq, Syria — he's been the first person to hold his hand up."
Nabi had put down deep roots in the community, helping to found a mosque and becoming president of a local Afghan association.
The retired engineer believed New Zealand to be a "slice of paradise", the Telegraph said.
Originally from Afghanistan, Nabi fled the war with Russia and brought his young family to New Zealand in 1979. He also had a daughter and nine grandchildren.
"His grandchildren really miss him and some of them don't even know that he is no more with us," Omar, 43, told Al Jazeera.
"This is a very difficult time for us and for everyone who lost their loved ones in this massacre."
"My father said how important it is to spread love and unity among each other and protect every member of the society we live in," Omar told Al Jazeera.
His father had also spoken about the end of his own life.
"He said the best place to pass away was during Friday prayers in a mosque."
Some Muslims believe Prophet Muhammad said there is a virtue in dying on a Friday, Islam's holiest day.
On Saturday, Yama Nabi, another of Nabi's sons, revealed that missing Friday prayers for the first time may have saved his life. He was running late when the massacre began.
"I parked my car and started running and saw police," Yama said.
"I was running and I saw women being shot, a little kid. I saw my Mum and she said Dad didn't make it."
Yama reached the mosque to find his friend Ramazan outside repeating, "Your father saved my life. Your father saved my life", the Independent Singapore reported.
"He jumped in the firing line to save somebody else's life and he has passed away."