Speaking from the altar O’Hare described the veteran gangster as one of Ireland’s “martyrs”.
He said that the 65-year-old was part of the “terrible beauty” of the Irish struggle against British colonialism.
“He had a real sense of justice that was matched by his integrity to do something about that injustice,” O’Hare said.
Kelly’s son Paul also addressed the large congregation to say his father was a loving man. As both men resumed their seats in Killester’s St Brigid’s Church there was a loud round of applause.
The shooting dead of Kelly (65) near his home last week was described as “evil” by Monsignor Alex Stenson.
The parish priest said that the killing was “a dreadful act” which
had violated his family and the entire community.
Kelly – who groomed many of the city’s most notorious criminals – was gunned down just yards from his home on Furry Park Road nine days ago.
This morning a lone piper marched ahead of mourners as his coffin was carried shoulder high from his home to the church.
Gardai kept a low profile as several hundred people, including some senior criminals, attended the Mass. Among them was terrorist Dessie O’Hare and a Tiger kidnapping mastermind who cannot be named for legal reasons.
As the coffin was brought into the church a woman sang Amazing Grace, accompanied by the church organist.
The chief mourners today were his five remaining sons and two remaining daughters. His son Robert and daughter Jenny predeceased him and his wife Ann died of cancer last year.
Monsignor Stenson, who lives on the same road as the slain gang leader, said his death by shooting outside his home was a “terrible crime” and he called for an end to all further violence.
He said the pain of his grieving family was very strong as they had lost a father, a grandfather and a great-grandfather.
To his family, he was extremely generous and was renowned as “a giver” who will be deeply missed by his loved ones.
His children remembered fondly their family holidays in Achill Island, which was one of Kelly’s favourite holiday destinations, he said.
The priest said that Kelly was in the midst of the community and it was a blessing that local people were able to go to his aid and pray with him as he lay dying on the ground.
He was buried in an ornate dark wood coffin that was engraved with scenes from The Last Supper.
Dessie O’Hare arrived at the home of the veteran gangster shortly after 8am to help with arrangements for the Mass.
Kelly (65) was close friends with O’Hare and the pair regularly drank together.
Among the chief mourners at the ceremony was Eamon Kelly's older brother Matt (68) who was warned by gardai that there was an active threat against his life just days before Eamon was shot dead.
Matt was ordered in 2002 to pay €3.6m in unpaid taxes after an investigation by the Criminal Assets Bureau.
O’Hare is one of Ireland's most feared crime figures and was also friendly with gang boss Martin ‘Marlo' Hyland, who was shot dead in 2006.
Kelly and ‘The Border Fox’ first struck up a friendship while each served lengthy sentences in Portlaoise prison.
O'Hare was released from prison in April 2006 after serving 19 years
for kidnapping Dublin dentist John O’Grady and has lived in Dublin since then.
He was released under the Good Friday Agreement after being given a 40-year sentence for kidnapping and mutilating John O'Grady in 1987.
A section of two of Dr O'Grady's fingers were hacked off by O'Hare using a hammer and chisel.
Since then O’Hare claimed he had reformed, taken up yoga and attended the Glencree Centre for Reconciliation in Co Wicklow.
Today’s service for Kelly took place in the same church where his wife Ann's funeral was held last summer.
She died following a long illness.
Afterwards, Kelly's body was taken to Glasnevin Cemetery for a private cremation service.
Sources say that despite his notorious gangland reputation, the father-of-nine was doted on by his family.
One man has already been charged with Kelly's murder while six others have been arrested and questioned about the high profile shooting.
Kelly previously cheated death when the Real IRA tried to murder him in September, 2010.
‘The Godfather' was lucky to escape when a gunman attempted to shoot him outside his Dublin home, but the revolver jammed.
That attempted murder was ordered by slain Real IRA terror boss Alan Ryan, who was shot dead on the orders of two north Dublin gang bosses known to Kelly in September of this year.
In the 1980s, Kelly specialised in armed robberies of cash and drink deliveries, and was behind some of the biggest bank heists of the decade.
In 1993 he was sentenced to 14 years in jail after he was caught with 997.3 grams of cocaine, worth an estimated IR£500,000.
The bust followed a surveillance operation led by current garda commissioner Martin Callinan.
It was one of the first times someone was busted with such a large amount of cocaine in Ireland.