Ousted former Prime Minister Tony Abbott has come under fire from prominent Australian Catholic priests after calling on Europe to shut its borders and deny entry to asylum seekers.

Speaking to British conservatives at the second annual Margaret Thatcher Lecture in London on Tuesday evening, Mr Abbott urged European leaders to follow his lead and stem illegal immigrant boats.

Surprisingly, the staunch Catholic - who spent three years at St Patrick's Seminary on Sydney's northern beaches before abandoning his clergical calling - called on conservatives to abandon the "wholesome instinct" to love thy neighbour as thyself, as it was "leading much of Europe into catastrophic error".

"It will require some force," Mr Abbott said.

"It will gnaw at our consciences, yet it is the only way to prevent a tide of humanity surging through Europe and quite possibly changing it forever."

Two prominent Australian Catholics have slammed the former prime minister's comments, claiming that to "love thy neighbour as thyself" is one of the central messages of the New Testament - with the passage central to Christian ethics.

Auxiliary Bishop Emeritus Pat Power, who headed the Catholic church in the Canberra-Goulburn diocese from 1986 until retiring in 2012, says he is "absolutely astounded" and "appalled" that Mr Abbott would use the Bible to preach his "narrow-minded" and "hard-hearted" message.

"I'm ashamed that a former Australian PM would be putting out a message like this," the retired Bishop told Fairfax Media.

"People will make their own judgements but that's completely at odds with what's at the heart of Christianity. I'm certainly offended," he added.

Similarly, human rights lawyer and Jesuit priest Father Frank Brennan has also shared the sentiments of his retired colleague.

"The appalling thing is that ex-PM Abbott has no right to preach to the world because having stopped the boats, he insisted on maintaining the facilities at Nauru and PNG," Father Brennan also told Fairfax Media.

"They are not are just harsh but cruel and they don't deter asylum seekers because we've now locked the front door," he said.

"Mr Abbott is confusing the situation regarding Australia."

Both members of the Catholic clergy cited Pope Francis' first visit outside of Rome in 2013 as an example of what the Catholic church is actually preaching.

In 2013, the Pontiff visited the Italian migrant island of Lampedusa where he called for a "reawakening of consciences".

Mr Abbott's comments are in clear contention with the world's most senior Catholic, who after visiting the migrant island said: "We have lost a sense of brotherly responsibility."

Prominent Australian Priests Slam Abbotts Use Of Biblical Passage