A new poll has found strong opposition among Christians to the legalisation of same-sex marriage.
The survey of more than 500 churchgoing Christians found that 83% are opposed to the Conservative Party's plans, with 75% "strongly opposed".
Ninety-three per cent said they were concerned that clergy would have to conduct homosexual marriages against their conscience.
There was also widespread fear about the impact of a change to the law on the status of marriage, with 85% saying that the value of marriage would be undermined.
Eighty-eight per cent believe schools will be required to teach the equal validity of same-sex and heterosexual relationships.
Seventy-eight per cent agreed that it would be harder to argue against "other novel types of relationship" such as polygamy.
More than half of the respondents - 57% - said the plans would make them "less likely to vote" for the Conservative Party at the next election. By contrast, no respondent agreed that the move would make them more likely to vote for the party.
The drop in party support among Christians will likely concern the Conservative Party at a time when it is looking to the church to help get the Big Society initiative off the ground and fill up the gap in social services left by cuts to spending.
Andrea Minichiello Williams, Chief Executive of Christian Concern, attacked David Cameron's commitment to legalising gay marriage.
“David Cameron has suggested that marriage is basically about commitment and it makes no difference whether this is between a heterosexual couple or a homosexual couple," she said.
"What possible authority does he have for making this claim and for trying to so radically re-define marriage?
"He is playing a dangerous game. He is about to find out that the large majority of quiet citizens are starting to say enough is enough and that the cherished institution of marriage cannot be dismantled in this way."
Most Christians opposed to plans to legalise same-sex marriage
Published 09 November 2011