A parishioner has claimed the priest at the church where Angelika Kluk's body was found was a liar who had "chased" and "harassed" her.
Angelika's body was found in a cellar under the church floor
The Polish student's body was found beneath a trapdoor in St Patrick's Roman Catholic Church in Anderston, Glasgow, in September last year.
Sarah Howie, 45, told the High Court in Edinburgh that Father Gerry Nugent knew about the trapdoor despite denying it.
Peter Tobin, 60, denies murdering and raping 23-year-old Miss kluk.
The former parish priest had claimed a sexual relationship with parishioner mother-of-two Mrs Howie, of Shaftsbury Street, Shawlands, Glasgow, before telling the trial he meant only intimacy but not sexual intercourse.
When advocate depute Dorothy Bain, prosecuting, told Mrs Howie that Father Nugent said he had a sexual relationship with her she responded angrily.
She said: "No he didn't, no he didn't. No sexual relationship with me whatsoever.
"He chased me if you like, he harassed me but we never had any sexual relationship whatsoever."
Miss Howie also claimed that Father Gerry knew seven or eight years ago about the trapdoor in the then bare floor which became the entrance to the place where Miss Kluk was buried.
She said: "The trapdoor was quite visible. There was no carpet on the floor then. It was very visible. It did not take Einstein to work out where it was."
Mrs Howie, who has been a regular worshipper at St Patrick's for 14 or 15 years and was married there, described how she and a friend went exploring.
They had heard tales of a possible crypt under the church, where former priests or bishops might be buried, and tunnels leading underground to the Charing Cross area of Glasgow.
Father Gerry gave them permission to look under the floor near the confessional, she said.
They took a torch and went into the void but found nothing of interest.
Mrs Howie also described how she and the other woman were kneeling at the trap door when Father Gerry approached.
She said: "He says to me in a joking manner 'Oh, did you find any bodies?' and we laughed and said 'Oh, no, nothing like that'."
The exploration happened about seven or eight years ago, she said, just after Father Gerry arrived at St Patrick's.
Angelika had been staying at St Patrick's Church in Anderston
Earlier in the trial, Mr Tobin's defence QC Donald Findlay repeatedly asked Father Gerry if he had known about the trapdoor at the time of Miss Kluk's violent death.
The priest denied it and told the lawyer over and over again: "I know nothing about her death or the circumstances of her death."
When told that Father Gerry had denied knowing about the hatch Mrs Howie said: "Most definitely he did."
Mr Findlay said: "That priest, that man of God lied not only to this court, he lied before his own god, if what you say is true."
Mrs Howie said: "Yes."
The trial also heard how on 6 October last year Detective Inspector Andrew McMillan, 37, interviewed Mr Tobin to be met with "no comment" to most of his questions about Miss Kluk.
Mr Tobin denies attacking Angelika between 24 and 29 September in St Patrick's Church, or elsewhere, gagging her with cloth and tape, binding her hands with cable ties, raping her, smashing her skull with a piece of wood or something similar, stabbing her 16 times in the chest and inflicting other knife injuries.
It is alleged that he then hid the body under the floor of the church.
He also denies that he told Glasgow police his name was Patrick McLaughlin, gave a false date of birth and address, and that he travelled to London and gave staff at the National Neurology and Neurosurgery Hospital in Queen's Square, London, another false name.
Mr Tobin also denies a breach of the peace between July and September last year by threatening Russian student Rebecca Dordi at St Patrick's Church.
The trial continues.