The death of George Nkencho is a "wound that can never heal", his funeral mass was told on Saturday.
Nigerian-born Mr Nkencho (27) was shot dead by gardaí outside his home in Clonee, Dublin on December 30th last.
His funeral and burial is now only taking place because of legalities around the release of his body.
Chief celebrant Fr George Adzato told Mr Nkencho's family that words alone could not explain the "pain and the sorrow" they felt over the killing of Mr Nkencho.
He quoted from comments Mr Nkencho's sister Gloria made to the media outside Leinster House in February.
“My mother has described it as a wound that can never heal. My family are forced to relive our trauma every day when we walk past his room, when we walk down the stairs and see where we stood as he was shot and killed.”
Fr Adzato said the pain of losing somebody at such a young age was particularly difficult. The gift of life was "very fragile and very precious. We hope to obtain old age, but this is not always possible," he told mourners at the Church of the Sacred Heart of Jesus in Huntstown in Dublin's north-western suburbs.
“When death comes as a tragedy, it robs us of our aspirations, it breaks our hearts and robs us of our joy. No parent expects to bury his or her child.”
He challenged the congregation and those watching online to “let the law do its work. The investigations are still ongoing. Let us be patient”.
In her eulogy, Gloria Nkencho said she hoped the public would remember him not for what had happened around the circumstances of his death but as a “brother, a son, a nephew, a best friend , a cousin, a teammate, a classmate, a protector, a partner”.
Approximately 100 people gathered outside the church to pay their respects to Mr Nkencho. A large banner was unfurled “Farewell George - Don’t forget, we’ll stand for justice and truth” and protesters handed out “Justice for George” fliers. There were also Black Lives Matter posters.
The organisers, who wore yellow bibs, handed out face masks to those who did not have them. Some wore facemasks with Mr Nkencho’s image on it.
In keeping with the Covid-19 regulations, only the immediate family attended the funeral service.
Mr Nkencho's simple white coffin was draped with the flag of the Insaka Glentoran Football Academy where he had trained as a footballer. At the exhortation of the stewards, a round of applause broke out as the coffin left the church grounds for burial afterwards in Mulhuddart Cemetery.
A Garda Ombudsman (Gsoc) investigation into Mr Nkencho’s shooting is ongoing. Members of his family have called for a public inquiry to be held.
Mr Nkencho was shot dead by the Garda Armed Support Unit outside his home after he assaulted a shop worker in a nearby supermarket, and an altercation with gardaí continued through a housing estate as he walked towards his home. He was armed with a kitchen knife and had, his family have said, been suffering from mental health issues in the months beforehand.