William Connelly broke down in tears as he told the Scottish Child Abuse Inquiry of his experiences at Smyllum Park in Lanark.
The 69-year-old, who stayed at the children's home from 1958, spoke of almost daily beatings by nuns and others.
He also claimed a priest would perform a sex act on himself when hearing confession.
Mr Connelly made the decision to speak publicly because he said he wanted his alleged abusers to "know that is me and not some anonymous guy".
He told the inquiry how a "dodgy" priest would make the boys strip off their "dirty" clothes and rub them in holy water.
Mr Connelly told how one of the nuns seemed to get enjoyment from regularly beating him with a hairbrush and kicking him with "pantomime" boots.
On one occasion, he said he was attacked with scissors and left with cuts to his scalp and hands.
Older boys, who were put in charge of the younger residents, were said to sometimes make them pick a stick which they would beat then them with.
Mr Connelly said he forgave the nuns, because he believed they were unhappy, but rejected their joint apology.
He then became aware at the hearing that one of his alleged abusers was possibly still alive.
Mr Connelly said: "She's a liar. One of the reasons I made the decision to do this was because I wanted them to know it's me and not some anonymous guy."
He then broke down in tears, before adding: "I was hoping she was dead, you've just told me she's still alive - she's a liar."
A statement was then read on his behalf which said he forgave the nuns.
Mr Connelly left the orphanage and after a number of years began some training, eventually going to university three times and gaining "qualifications coming out of my ears".
He has volunteered and worked for social justice charity Nacro.
Another witness, who cannot be named, told how he was sexually abused in a bathroom at the home by a worker when aged under 10 years old.
The alleged attacker was said to have lived at the home until he was 16 before being given a job there because he had no relations outside.
After the incident, which was said to have taken place in the late 1950s, the witness told how he was too scared to go to the bathroom by himself.
In December 1959 he returned home to his parents before going back to the institution in the spring of 1960.
Having described the care home as "like a concentration camp", the witness broke down in tears when recalling when his parents told him he would have to return to the home.
In opening statements to the inquiry on Tuesday Solicitor Gregor Rolfe, counsel for the Daughters of Charity, who ran Smyllum, reiterated the apology made by the order at the conclusion of the first phase of the inquiry.
Their statement said: ''As Daughters of Charity our values are totally against any form of abuse and thus we offer our most sincere and heartfelt apologies to anyone who suffered any form of abuse in our care.''
The inquiry continues.
