David Black was a prison officer who was dedicated to improving society, mourners at his funeral have heard.
The peace-loving father of two wanted prisoners to leave as changed men, his family minister said.
Inmates at Maghaberry jail were among those who paid tribute to the victim in recent days.
The Rev Tom Greer said: "David Black was a man of honour and principle, a man of kindness and generosity, a man committed to peace and prosperity in Northern Ireland - all those things completely the opposite of the murderous thugs and bloodthirsty criminals who took David's life."
He said Mr Black was a regular church attender and friend to many, adding: "It is so terrible that evil men with such hatred in their hearts should rob us of a great man like David with love and kindness in his heart.
"It is so tragic that a man with a distinguished career behind him should be taken from us perhaps just a few weeks from retirement."
The minister said prisoners had called him to express support and written a letter praising Mr Black.
"David viewed his work as something that was meant to improve society. He wanted those who came into prison to leave as changed men," he said.
"And one of the things he was concerned about to that end was their spiritual well-being.
"He was always adamant that prisoners have the opportunity to meet with a pastor or a chaplain who would address the real issues in a person's heart - for society only changes for the better when people's hearts are changed."