But over the Easter weekend Mr Cameron has allowed his message to become a little fuzzier.Writing for Premier Christianity, a Christian magazine and radio station, the prime minister talks about "hard work, fair play" and the importance of Christian "values".
Mr Cameron's article, and the reaction to it, highlight the dilemma he faces as he seeks re-election.Related topics United Kingdom Christianity Anglicanism Culture and lifestyle ReligionSome 33m people are Christians in Britain.
After the Tiananmen Square massacre of 1989 many disenchanted democrats turned to Christianity: six of the 30 or so student leaders of the protests became Christians.
There's 'The Uncle', the mysterious man obsessed with Christianity who used to pick up prostitutes, talk to them about God and give them drugs.
Almost six centuries after most of them converted to Christianity, a rabbinical court has declared that descendants of a "lost tribe" from the Spanish island of Mallorca can once more be considered Jews.
This is not quite true – Newton continued being a slave trader after he had converted to Christianity, did not speak out against slavery until 30 years after he left the trade, and became a rector.
Monrad is moving on to New Zealand to "convert the savages" to Christianity.
For years, Catholic bishops had already been sniping from the sidelines at Merkel – a divorced, childless Protestant – saying that many of her policies (on stem cell research, for instance) had no grounding in Christianity.
"Christianity and the Incas were wedded here," Señor Rivas says.
Christianity and the church have always been part of that story.
In the case of two major sponsors, this meant imbuing them with evangelical Christianity, and in another famous case it meant having a fully functioning stock-exchange trading floor in the basement, to show pupils what really matters, which is, of course, making lots of money.
