Building a new meeting hall for an evangelical Christian group could harm community integration, a group of villagers has warned.
Objecting to the conservative religious group's planning application, some people in Mobberley, Cheshire, said the Exclusive Brethren are too "insular".
Concerns over traffic and the impact on the greenbelt have also been raised.
The Brethren said they "contribute to local communities in friendliness and with enthusiasm".
The group, also known as the Plymouth Brethren Christian Church, had an estimated 20,000 members in the UK in 2011.
Followers adhere to a set of strict rules based upon their interpretation of the Bible.
In avoiding anything they perceive to be sinful, members cannot watch television, listen to the radio, or go to the cinema.
The Brethren said they have outgrown their current regional headquarters in Hale, Greater Manchester.
'Practice of separation'
A number of Mobberley residents have written to Cheshire East Council's planning department arguing that the group's members "are discouraged from contact with those not belonging to the Brethren".
They fear followers "are likely to have little or no involvement or integration with the local community".
The organisation has a "practice of separation" meaning "social fellowship" only takes place within the group.
The Brethren insist this rule "does not preclude interaction in the broader community".
In a statement given to the BBC, they said: "Interaction is extensive both in the workplace, towns we live and in our charitable work.
"Members live in ordinary residential areas and interact with society in a normal way."
The Brethren's proposed meeting hall, on the site of Mobberley Riding School, would have a capacity of at least 500, according to documents submitted to the council.
Neighbour Sarah Irlam said: "It's a very modern-looking building, it's totally unacceptable for the greenbelt area.
"The infrastructure is just not there for this kind of building, the traffic it will incur to the village is just going to be crazy."
The group said most meetings would not see the building used to its full capacity, meaning the amount of traffic generated will be "similar" to current levels.