A young boy was beaten "black and blue" after seeing two nuns in an embrace, an inquiry has heard.
A man said he was six or seven when one of the nuns lashed out at him in a boiler-room at Smyllum Park orphanage in the 1960s.
He told the Scottish Child Abuse Inquiry the "vicious" assault left him with blood coming out of his ear and nose.
He described beatings from the nuns as "thunderous".
The witness, who cannot be identified, told the inquiry of his experiences at the Lanark home which closed in the 1980s.
He said he moved to the orphanage, run by the Daughters of Charity of St Vincent de Paul, in the mid-1960s, where he was never given any love, affection or praise from the nuns and staff who ran it.
Physical abuse in the form of slaps and kicks were routine "for trivial stuff", he told the hearing in Edinburgh.
The man recounted one incident in which he walked past a boiler-room and went through an open door to have a look inside.
'Black and blue like a boxing match'
He said: "There were two nuns in there and one nun had her arms around the other one, at which point she turned around and gave me a right good hiding.
"I'm talking about punching, kicking, pulling my hair.
"I distinctly remember there was a boiler and it had a flame coming out of it, a flame thrower... she put my face really close to that.
"I can still remember my hair getting singed, my eyelashes, and the smell of singeing stayed with us for quite a while after that."
When he "woke up" from the attack, he said he had "blood coming from my ear, blood coming from my nose."
"For days after that, I was black and blue, like being in a boxing match actually."
He said he wondered for a long time what had caused the nun to be so "nasty" until he found out about one of television's first lesbian kisses on the soap Brookside.
"She was obviously kissing another nun, that's what I think," he said.
He told how he was later moved to another institution in England.
During his time there, he experienced sexual abuse at the hands of a trainee priest, the inquiry heard.
He told how the enforced move really affected him, having "robbed" him of his Scottish identity.
Another witness told the inquiry he has a fear of nuns after suffering physical, emotional and mental "torture" at Smyllum.
The man - whose name cannot be disclosed - spoke of regular "thunderous" beatings at the hands of the nuns tasked with looking after him.
The witness told how he was taken to Smyllum for a time at the age of four following the death of his mother.
He said the nuns would beat him, kick him and strike him with implements such as wooden coat hangers.
"The punishments were frequent and the beatings were thunderous," he said.
He also spoke of verbal abuse from the "callous" sisters, telling the hearing: "The nuns would say things like 'your ma's left you for good'."
He said: "Being there at Smyllum, it was physical, emotional and mental torture."
The witness told the inquiry he has "an absolute fear of nuns".
The inquiry, chaired by Lady Smith, continues.