St John's Cathedral appears to be fighting a losing battle against plagiarising priests - a practise that has already led 17 families of believers to leave the Anglican church.
A former parishioner at the Emmanuel Church in Pok Fu Lam, a St John's affiliate, said four priests were guilty of using sermons from the internet and preaching them as if they were their own.
He said they had been doing so for 18 months.
The Very Reverend Matthias Der, the new dean of the cathedral, confirmed that some priests had persisted with their plagiarism despite his warnings against the practice at his first meeting with them in September.
"There is still bad practice in some of the priests," Der said on Friday, without confirming the number of clergy involved.
"I told my clergy that any kind of use of outside sources needs to be attributed," Der said of the September meeting.
"I understand that when we do research, we will look at other people's writing, but if we are using direct quotes then we need to attribute them. Plagiarism is not acceptable."
Several priests are still failing to cite their sources. Der said: "When I learned of this a few weeks ago, I [again] made it clear to my colleagues that it was not acceptable."
The former parishioner, who had attended Emmanuel Church for almost a decade, said he left recently because of the dishonesty of the priests and the inaction of the church.
"It is very disappointing to see the extent of plagiarised sermons published on the websites of St John's Cathedral and Emmanuel Church, even though this was brought to the cathedral's attention 18 months ago," he said.
The church keeps an online audio archive of its sermons. It shows a number of priests have included direct quotes from sermons or church newsletters found online with no attribution of the original source.
The Sunday Morning Post contacted some of the priests accused of plagiarism, but they refused to comment.
Two of them told the Post to speak to the dean, while another denied the allegation.
Der said the priests accused of plagiarism "all have different reasons" for their actions.
He said he was surprised when he realised what was happening.
"I had heard of [plagiarism by priests] before, but I had never met anyone who had done it," he said.
Der said plagiarism called into question a person's honesty.
"If we borrow, we need to attribute and that is the part they didn't do," he said. "It's an unfortunate issue and it's not something I condone or support."
Der said he always advised his clergy to prepare original sermons.
"While we research and look at other sources, the sermons we deliver are meant to be from our own preparations," he said.
Referring to the departure of the 17 families because of the ongoing plagiarism by priests of the church, he said: "Losing a single parishioner pains me, but unfortunately that has happened.
"Under my watch, this is an issue I take seriously and I'm doing my best to amend it.
"I trust my colleagues will comply or there will be more serious consequences."