The vicar of Putney has an uncomfortable feeling that his son should have had a bris.

The Reverend Dr Giles Fraser, a regular contributor to BBC Radio 4’s Thought For The Day, has two girls and a boy with his Scandinavian wife, Sally. So far, so normal, except for the fact that his father is Jewish and he himself was circumcised.

“There’s a part of me that still feels some sense of guilt about this,” says the 44-year-old Church of England priest, who also teaches philosophy at Wadham College, Oxford. “When we had my son, the first thing I thought was: ‘We must get him circumcised.’

“Whenever we travelled down Abbey Road [in St John’s Wood, north-west London], my mother always pointed out the second-floor flat where the rabbi circumcised me. My wife thought it was not a good thing and I had to justify to myself why I thought it was important. But for me it was an extraordinarily powerful thing.

“The theologist Emil Fackenheim wrote this famous doctrine called the 614th Mitzvah, saying we should not give Hitler posthumous victories. I just thought to myself: the story of my family is part of this great story of hope, part of this story of Jewish people surviving the threat of annihilation. It was an emotional thing, rather than a spiritual thing. Of course, I would have been Jewish enough for Hitler, and so would my son.”

So Dr Fraser, who is “team rector” at his south-west London parish overseeing two churches, St Mary’s and All Saints, became the last in the Friedburg line (the family name was changed to Dr Fraser by his grandfather during the Second World War), to be circumcised.

“My dad’s family were glamorous north London Jews,” he says. “The Friedburgs had been in Britain since the 18th century. My great grandfather was secretary to the Board of Deputies. My grandmother was Miriam Beckerman.

“She was a dressmaker who lived in St John’s Wood — it did seem very glamorous to me, growing up in Leicestershire. It was extremely urban. The food was always excellent. There was a sense of ‘these people are our people’. There was no religious side to it — it was about food and family.”

Like most grandparents, Miriam Beckerman was kvelling when her grandson took the cloth 16 years ago, after finding religion while studying politics at Oxford. It did not seem to matter that Dr Fraser would be wearing a dog collar rather than rabbinical robes.

“My gran was ever so proud when I became chaplain of Wadham,” says Dr Fraser. “‘My grandson, the priest’, she would say. When I went to theological school she said: ‘Make sure you learn your Hebrew!’ I did her funeral. I did it in a crematorium in Cambridgeshire where I was working as a priest. I said kaddish.” His father was an RAF officer who met his mother when he was posted in Leicestershire. “My mum married my dad because she was a philosemite,” he says.

“She was interested in meeting a nice Jewish boy and marrying him. She grew up in the Midlands in a small village and Jewish people were seen as something romantic and exotic. She has become been most pro-Jewish in the family. She makes cold fried fish — it’s absurd.

“My dad wanted to blend in. Me and my two brothers went to a posh school, Uppingham in Leicestershire, where Christianity was part of the world view. We grew up with Christianity in the background. My brothers went into the City, I got God.”

Dr Fraser acknowledges that his Jewish roots have meant that following his religious convictions has not been entirely straightforward.

“Intellectually, Christianity is my theology. I don’t regret anything about being a Christian because that is where I am in terms of my belief system,” he says. “It’s an internal struggle. I don’t think there’s a way of resolving it. I live with the wound. It’s just as much a personal story about where you come from.”

Although he does not in any way support Jews for Jesus or other groups which seek to convert Jews to Christianity, he prefers to see the similarity between Jews and Christians.

“I have a very strong sense of the Jewishness of Christianity,” he says. “I would probably know the Hebrew scriptures and the theology considerably better than many secular Jews of the world. To that extent, I probably have more in common with the rabbis. I identify quite strongly with friends who are Jewish. I had to do a Jewish wedding with rabbi recently. Jesus was Jewish and Hebrew scriptures are part of Christian scriptures.

“I really don’t want to be Jews for Jesus. I’m just a priest who happens to have a Jewish background, with a strong sense of identity. I’m not in the least bit interested in converting Jews to Christianity. There’s a part of me that thinks it’s really wrong. I’m painfully aware of the way in which Christians have been involved in false conversions and pogroms. Christianity has a long history of oppression with regard to Jews. It invented antisemitism, so with all that disgraceful history I can’t accept that and I find it difficult to pull it apart from all of that history.”

When asked if his decision, consciously or unconsciously, to become a priest was to feel a sense of belonging, he agrees it might have been part of the reason.

“The number of people who say: ‘Clearly you’re not Jewish’ — even though it’s entirely true, it feels like a rejection,” he says.