Dr Richard Scott is a Christian and GP at Bethesda Medical Centre in Margate, Kent, who says that he offers prayer to patients occasionally - estimating he offers prayer to about one in every forty patients.
The GMC, which says it protects patients and supports healthcare providers by improving medical practice, wrote to Dr Richard Scott on 7th June saying it had received "some information" from the National Secular Society and would begin a fitness to practice investigation.
The National Secular Society raised concern after someone they say was described as "highly vulnerable" by an acquaintance was made to feel uncomfortable by his use of prayer.
The NSS said: "The acquaintance told the NSS that the patient felt unable to express discomfort and was not able to raise the matter formally or change GP practice."
Tim Dieppe from campaign group Christian Concern, which is supporting him, told Premier's News Hour that Dr Scott always asks his patients if they're open to discussion: "Sometimes they're not, and that he respects that and other times they are and they engage in the conversation.
"The National Secular Society are being very aggressive in saying he should be struck-off for having conversations about spirituality once he's done his clinical GP responsibilities in the appointment with his patients and I think that's way over the top. He's a very good doctor with long standing experience and what's wrong with him talking to patients about the benefits of prayer?"
When asked if he's aware that there are people who might not feel comfortable with prayer, Mr Dieppe said: "Of course he's aware of that and of course he always asks permission and tries to sensitively see if people are open to that or not.
"Some of the people do say no and he respects that."
Christian Concern also criticised the National Secular Society for hiding behind a vulnerable patient, with Mr Dieppe saying: "I think it's somewhat absurd this vulnerable patient is now being used by the National Secular Society...to make a case to say that this doctor should be dismissed because of these alleged feelings in this alleged statement by this patient.
"I think that's very odd that this should be taken seriously, really."
Speaking about the power of prayer, he said: "The fact is that prayer makes a difference. The fact is we are spiritual beings as well as physical beings and if you're showing concern for a patient as a whole person you'll want to bring spirituality into it sometime, when you feel that that's appropriate.
"Sometimes they'll benefit from it and you'll see their lives changed and impacted by prayer.
"It's kind of crazy that they're having an investigation on the basis of hearsay of what a patient claimed happened in a conversation. There's no complaint about, medically, what he's done or the diagnosis or what the clinic is offering that is just hearsay about a conversation at this stage.
"I think that really it should just be dismissed."
In 2012, Dr Scott faced similar criticism and received a warning from the GMC for evangelising to patients.
The General Medical Council told Premier they have to investigate a doctor's ability to practise if there are concerns made which threatens the public's confidence in the profession.
They added that many of their investigations do not result in action and that the doctor has the opportunity to give their own comments.
The GMC aim to complete investigations within 12 months.
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