Christians were subjected to discrimination and exclusion from public life by the former Labour Government, according to an influential Conservative website.
Writing on the Conservative Home blog former aid worker Dr Martin Parsons also cautioned that the Conservative Party’s attitude towards Christianity may have cost them an overall majority in this year’s election.
Dr Parsons warned that Labour had isolated millions of Christian voters by attempting to introduce laws which would have further marginalised their faith.
He slammed Labour for trying to introduce a law, in the form of the 2008 Criminal Justice and Immigration Act, which was so badly worded that it would have exposed Christian preachers to prosecution.
The threat was only averted after former Home Secretary Lord Waddington successfully campaigned for an amendment, backed by The Christian Institute.
Commenting on the law Dr Parsons said: “The amendment was important as a number of Christians including OAPs, Christian ministers and a bishop have been subjected to ‘intimidating’ police questioning and even arrest as a result of complaints made by gay rights activists who disagreed with their beliefs.
“In each case it was evident from the outset that no actual ‘crime’ had been committed.”
Dr Parsons also criticised Labour’s failed attempt to remove the rights of churches to appoint people who adhere to biblical standards through the party’s highly controversial Equality Act.
He warned: “The proposed ‘anti discrimination’ legislation was the equivalent for the church and Christian organisations of legally requiring the Conservative Party not to discriminate against someone with socialist views when selecting parliamentary candidates, only it was not pragmatic political beliefs that were at stake, but deeply held religious beliefs about morality.”
Dr Parsons also warned that the “widespread perception that Christians were being systematically discriminated against” had led voters to turn away from Labour.
He added: “With between 3 and 4 million practising Christians who were deeply concerned about this issue there was the potential for this to significantly affect the outcome of the general election.
“This was the equivalent of more than 4,500 voters per constituency.
“If only 1,000 of those 4,500 voters had switched from voting Labour (or Lib Dem in Lib Dem held seats) to voting Conservative, then we would have gained an overall majority.”
But Dr Parsons warns that many Christians were left disappointed by the Conservative Party’s attitude towards Christianity in the run up to the election.
Just before the election Chris Grayling, then the Shadow Home Secretary, said that Christians who run B&Bs in their own homes should be allowed to exercise their conscience over who is allowed to stay.
He was later made to retract his comments, and Dr Parsons warned that this created a “huge sense of disappointment” among many Christians.
And he said that this had only been heightened by David Cameron’s deselection of a Christian Tory candidate who disagreed with homosexual conduct.
Dr Parsons added: “This action by the Scottish Party created a strong impression among many Christians that the Conservative Party was intolerant of Christians and prepared to actively discriminate against anyone holding orthodox Christian beliefs on sexual ethics to the extent that they would prevent any such person from becoming a Conservative MP.”
Last month a candidate for the Labour Party leadership said that the Party looked “ridiculous” for creating a culture which marginalised Christians.
Andy Burnham said his party needed to apologise for the culture that saw nurses being attacked for wearing a cross.
However he also criticised the Church for getting involved in moral issues, saying it had been “too black and white”.
Mr Burnham made the comments earlier this month in Methodist Central Hall at a hustings hosted by the Christian Socialist Movement.