Five kilometres across town on one of the city’s most famous shopping streets, a handful of Westerners join the congregation filing in for a 4pm English service at state-run St Joseph’s Church.

Inside the grand grey Wangfujing church originally built by Jesuit missionaries in 1655, security cameras scan the people in the pews and priests at the altar.

On the surface, the church and the embassy function room offer the same services – they are both in English, they follow the same mass format and they would be familiar to Catholics anywhere in the world.

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Beijing has four state-run official churches offering services in English, but many foreigners have turned to unofficial institutions in search of a sense of community and a space where they can freely discuss their faith.

Beijing cut ties with the Vatican in 1951 and set up the Chinese Catholic Patriotic Association (CPA) in 1957 to ensure believers toed the Communist Party line.

Now, China’s estimated 10 million Chinese Catholics go between government-backed churches run by the CPA, or illegal underground churches loyal to Rome. About 60 per cent of mainland Catholics worship in state-sanctioned churches.

While under far less scrutiny, foreign practitioners of Catholicism are given just one government-sanctioned option: going to a state-run church overseen by bishops approved by the party.

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Chinese law states “aliens” are allowed to take part only at lawfully registered places of worship.

Canadian Ian Johnson is a Beijing-based journalist and lecturer who has attended both kinds of services for foreigners and likens the state offering to an assembly line.

“There are five services a day and everything lasts for exactly an hour, then – bang! – your next one starts,” Johnson said. “You don’t really have any personal relationships with the priest or the congregation.

“People have said it is a more impersonal experience, or they feel they are just going through the motions. It is less engaged.”

It is an assessment echoed by Brent Fulton, founder and president of ChinaSource, a research platform of Christian communities in China.

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“In the official church a foreigner can come, but their involvement is limited to sitting in that service on a Sunday,” Fulton said.

At an unofficial church they can get involved by teaching Sunday school, singing in the choir or leading a Bible study.

That lack of community prompted Sarah, a 24-year-old American student in Beijing, to seek out an unofficial church.

“If [St Joseph’s] was my only outlet for going to mass and worship, my faith life would probably wither,” Sarah said. “I would struggle. But with my private community, it is more intimate, so the homilies are more meaningful to me and a lot of dialogue is exchanged between the people that attend.

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“When I go to the private space it seems the priests who preach during the homily have more freedom in what they say and it’s a more open and honest homily.”

Leaders of the embassy church declined to be interviewed, citing the sensitivity of the issue.

Although unofficial foreigner-only churches are not allowed in China, they are not hard to find. They are tolerated by the government, which turns a blind but watchful eye to the unsanctioned activity.

“As long as nobody asks [the government] a question, they don’t care, but the people doing it are extremely cautious,” Johnson said.

But some foreigners are content with the official services.

“Every Sunday there is a very well-prepared English mass with an excellent choir that sings in both English and Latin,” Michele Ferrero, an Italian Catholic priest, said of the Cathedral of the Immaculate Conception, or “South Church”, in Beijing he regularly attends.

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Ferrero has taught Western classics at Beijing Foreign Studies University since 2009, having previously taught at a seminary in Shanghai.

“Worshipping itself is no different in Beijing than anywhere else,” he said.

Fr Hugh O’Donnell, an 83-year-old Taiwan-based priest who belongs to the Congregation of the Mission and has travelled to and from the mainland for more than two decades, agrees. He said the English mass at South Church was run by Chinese priests and “has come to a pretty high level of competence”.

“[Visitors will find] some good preachers, [who] prepare well and do a terrific job,” O’Donnell said.

But foreign priests are not allowed to say mass and bishops are appointed by the state, creating a “stigma” and misplaced perception that official churches “aren’t genuine”, Fulton said.

Foreigners could pursue a third option – attending “underground” services with Chinese Catholics; but doing so posed a high risk for local worshippers.

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“We tell [foreigners] not to go to the unregistered [Chinese] churches, because that does create problems for the people there,” Mulroney said. “They could get into quite big trouble if foreigners are seen turning up.”

The church could be closed and priests could be arrested or harassed, he said.

“If there are foreigners going, with any hint of bringing information in or something similar, there could be trouble for the people. That’s what you have to balance,” Johnson said.