Members of the clergy are being advised to take off their dog collars when they are on their own, to reduce the risk of being attacked.
There is no need to wear the dog collar in supermarkets, advice says
National Churchwatch, which provides personal safety advice, says vicars are attacked more often than professions such as GPs and probation officers.
The organisation's Nick Tolson said all clergy should consider the advice, including the Archbishop of Canterbury.
The group also produces security advice for all UK churches and churchworkers.
In the past decade, five vicars have been murdered.
And a 2001 academic study also found that 12% of clergy had suffered some form of violence.
In a survey of 90 London clergy Mr Tolson carried out last year, nearly half said they had been attacked in the previous 12 months.
One vicar, from Willesden, north-west London, said his vicarage had been machine-gunned - but still did not believe he had experienced violence.
Mr Tolson said: "For some clergy this is real radical stuff. The argument against it is it's their witness in the community - their way of saying, 'hello, I'm the vicar'.
"That's fine when you're being the vicar. If you're visiting someone or going to an old people's home, wear your dog collar."
He added: "When they are on their own, and when they are off duty - for example when they are doing their shopping in Tesco on their own - there is no need for them to wear their dog collars.
"All that does is to attract people who see the dog collars, and if they are motivated towards violence, it puts them [clergy] in a very difficult situation."
National Churchwatch also says that most police forces do not specifically record crime against places of worship.
However, it says that crime against churches continues to be a problem, and there is "plenty we can do to help reduce it".