Ross Francis Murrin, 52, has pleaded guilty to 17 charges over the sexual abuse of eight Year 5 and 6 students at his Sydney school in 1974.
He had been molested over a period of almost 10 years by his cousin and was just 18 when he began teaching as a Marist brother in the 1970s, the court was told.
Murrin taught at various schools in the Marist system until the allegations came to light in 2002.
One of his victims died of a drug overdose in 1987 aged 22, and his father said his abuse by Murrin when he was 10 completely changed him.
"This revelation (caused our family) total emotional distress and heartbreak," the man told Sydney District Court on Friday.
"I'm now in a position to understand my son's disinterest in school matters."
He became "secretive and reclusive" and withdrew from the family, and developed a substance addiction to mask his low self-esteem and feelings of little worth.
The boy entered rehabilitation at 18 and left the program 40 times in five years, unable to overcome the demons of his past.
"The family was extremely fearful of his instability, that it would result in the loss of his life, which it did," his father said.
The revelation of Murrin's abuse sparked a "chain of detrimental events" for the family, leading to a "meltdown", he said.
"The effect of this knowledge of the abuse was far-reaching. Our grand-children in Catholic schools, we fear that they are suffering.
"Our belief has been rocked in all things Catholic."
Another of Murrin's victims said the attacks had destroyed his faith in God.
"It was only in my adult life that I realised that Ross Murrin betrayed all of us ... everyone in our class of about 30 students," he said.
"He betrayed the local community, he betrayed the NSW state government, the Marist brothers order, the Catholic church and most of all our parents."
"My parents entrusted us to the Catholic system of education, they paid with their blood, sweat and tears to get my brothers and I through a more ethical system ... the same system that was supposed to protect us, the same system that my parents had trusted so much."
"I have not reached out and spoken to God for a long time ... I hope God and my father can forgive me for my many years of absence from our faith," the victim said.
Murrin's treating psychiatrist Dr Christopher Canaris said he was admitted into a special program for sex-offending clergymen by the Marist brothers when complaints were first made against him in 2002.
He was suspended from ministry and underwent an eight-month intensive residential rehabilitation program, Dr Canaris said.
"My strong impression is that he is very aware that what he's done was wrong," the doctor said.
"He's certainly expressed his sorrow for what's happened."
Judge Helen Murrell said she was unlikely to consider anything less than a full-time jail term, and revoked Murrin's bail on that basis.
He was remanded in custody and will be sentenced on February 29.
+++++++++++++++++++++++++++++++++++++++++++++++++++
No responsibility or liability shall attach itself to either myself or to the blogspot ‘Clerical Whispers’ for any or all of the articles placed here.
The placing of an article hereupon does not necessarily imply that I agree or accept the contents of the article as being necessarily factual in theology, dogma or otherwise.
Sotto Voce