As the top lawyer at the Office of Fair Trading, Brian McHenry has been instrumental in protecting consumers against unfair pricing and sharp dealing. Now he is on a mission to save their souls.

Mr McHenry, 56, has informed colleagues that he will be retiring early from his post as general counsel to become a deacon in the Church of England. He will step down as soon as his successor is appointed, which could take until the end of the year. The position has not yet been advertised.

"I've long had this thought niggling in the back of my mind that this was not where I wanted to be," Mr McHenry told Times Online.

Mr McHenry has spent his entire professional life as a government lawyer since joining the Treasury Solicitor's department in 1978. He served two stints at the Competition Commission, including as chief legal adviser from 2000 to 2004, and was the solicitor to two major public inquiries in the 1990s: the North Wales Child Abuse Tribunal and the BSE inquiry.

As general counsel to the OFT, he is chief legal adviser to the board and oversees almost 100 lawyers. He was instrumental in a recent reorganisation that has seen lawyers given a much greater role in the regulator's frontline operations, and created its first litigation department. In 2005-06, he earned between £105,000 and £110,000 in basic salary.

But Mr McHenry, who describes himself as a mainstream Anglican and not a "bible thumper", has also been active for many years in the Church of England as a lay reader and a member of the General Synod.

He had been feeling an increasing calling to serve God since his early 40s but had at first "run away from it", he said. A few weeks after joining the OFT in July 2004, however, he attended a church service at which a sermon about the importance of higher orders touched him deeply. "It really did feel as if God was speaking to me," he said.

Mr McHenry enrolled at the Southeastern Institute for Theological Education and began attending weekly evening classes and regular weekend retreats. His training included accompanying a chaplain to two nightclubs - Ikon and Jumpin' Jaks - in Maidstone, Kent, where they attempted to engage staff and revellers in spiritual conversation. "People were only too happy to talk, particularly the door men. I began to realise that all chaplaincy work is just getting to know people."

Mr McHenry will continue his studies full time, living off his civil service pension, until mid-2008 when he will be ordained as a deacon. If all goes to plan, he will become a full priest a year later and then apply to take over a country parish, working three or four days a week in exchange for free accommodation and all expenses paid.

It would mean giving up a lifestyle that includes a three-storey Victorian terraced house in South London and three Arsenal season tickets, but Mr McHenry says he has the support of his wife and two adult sons. His wife will continue to work as a doctor at King's College Hospital in south London.

The most daunting thing, he says, is leaving London after living in the city all his life.

Mr McHenry grew up in Streatham, the son of a militantly left-wing father who was opposed to organised religion. But while attending Oxford University, where he studied history, Mr McHenry grew homesick and sought respite at the New College chapel. From there, he became more and more involved with the church and eventually the rest of his family, including his father, followed.

Mr McHenry said he will miss the law but has always enjoyed the "people" side of the job more than "burying my head in legal books".

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