Public health expert Dr Gabriel Scally has said it is "wrong, irresponsible and unChristian" of a Co Cavan priest to continue to say mass in his parish despite gardaí informing him he is in breach of public health guidelines, after allowing up to 50 people attend Mass at his church.
Dr Scally, President of the Epidemiology and Public Health section of Britain's Royal Society of Medicine, said he was "quite shocked" to hear Fr PJ Hughes was determined to keep the doors of his church open in Mullahoran for mass despite being asked not to by Church authorities and the gardaí.
Speaking on RTÉ's Today with Claire Byrne programme, Dr Scally said that while he appreciates people can have strong religious views and faith, this can be exercised in individual worship and not collectively in the current times.
He said it is '"just wrong" and a "delusional thought" to think that faith will protect one from contracting Covid-19.
He said that the priest is putting many elderly and vulnerable people at risk of infection and also risking enormous spread in the community.
Dr Scally said there is a really strong record across the world "of people who believe that in some sense because they are involved in active religious worship they are exempt from the virus" and this has led to death and enormous spread in some cases.
Speaking on the same programme, Fr PJ Hughes said: "The official Church has said close the doors and obey the law; I am sorry I can't accept that.
"I don't think I broke the law. I didn't think someone practising their faith would be in breach of the law in any country," he said.
Fr Hughes believes it is a breach of people's constitutional right to be prohibited from attending mass.
"It's a divine right. We have a divine right to worship God. Show me a law that says I'm wrong."
He is calling for the Minister for Justice and the Garda Commissioner to apologise to Catholic people who want to practise their faith.
Fr Hughes said he will continue to say mass every day but he will not be "publicising the time" that it is due to begin.
"It is their decision. I am not responsible for them coming to the church."
Under Level 5 restrictions churches are closed for public worship, and can only take place online.
Referring to the visit to him by gardaí, Fr Hughes said: "They told me they had a file prepared for the DPP, and were going to prosecute me because I had broken the law, and would be fined €2,500 and go to jail for six months.
"And I said, 'I don't think I broke the law'."
Meanwhile Archbishop Eamon Martin, Catholic Primate of All Ireland, has said the decision to close churches across Northern Ireland from 27 November for two weeks is "a great disappointment".
In a statement, he said it was "contrary to the assurances given to faith groups at a meeting just last week at which we were praised for our attention to safety and public health".
Archbishop Martin added: "I seek urgent clarification on the question of whether churches may open for individual visits and private prayer.
"I cannot understand how a person may still go to an off-licence to buy alcohol but might not be permitted to visit and sit in quiet solitary prayer in a large church.
"The right to do this is particularly important for Catholics."