Fr Michael Higginbottom, 74, is accused of subjecting the teenage boy to repeated sexual abuse when he worked as a teacher at St Joseph's College in Upholland, Lancashire, in the late 1970s.
Liverpool Crown Court heard the boy, aged 13 or 14 at the time of the allegations, said he would be struck with a strap if he did not attend Higginbottom's living quarters, where much of the abuse was alleged to have happened, at appointed times.
The boarding school, which has now closed, was attended by boys aged 11 to 18, many of whom were considering a career in the priesthood.
David Temkin, prosecuting, said the alleged victim had described the school as a "cold, dark and forbidding place".
He added: "He told the police that for him it was the venue for 'mental, physical and sexual abuse'."
The defendant worked at the school as a priest and teacher and was "therefore in a position of trust", Mr Temkin said.
"The prosecution say that he breached that trust in a spectacular and horrific way," he added.
About a week or so after the boy's arrival at the college he was invited into Higginbottom's living quarters where the defendant locked the door and ordered him to undress before sexually assaulting him, the court heard.
Mr Temkin said after the first assault Higginbottom told the teenager things would "get easier" for him at the college.
The victim revealed the allegations to a friend in 2013 and was encouraged to report them to the police.
When interviewed, he was unable to remember how many times he had been sexually abused.
Mr Temkin said: "All that he was able to say to the police was that it happened 'a lot'."
When Higginbottom was arrested at his home in Newcastle in 2015 he told the police the allegations were "total lies" and he could not remember the complainant.
Higginbottom, of West Farm Road, Newcastle, denies four counts of indecent assault and four counts of buggery.
The trial continues.