A Roman Catholic bishop is to use his Christmas message to take a political sideswipe at the coalition government, addressing its intentions to redefine the institution of marriage.
During midnight Mass at Shrewsbury Cathedral the Rt Rev Mark Davies will tell his congregation that the proposals to push through a Bill to legalise same-sex marriages are casting shadows over the country.
According to the Daily Mail and the Daily Telegraph, the Bishop of Shrewsbury will also compare coalition plans to the ideologies of Nazism and Communism, which threatened "Christian civilisation" in the name of "progress".
He is expected to say that supporters of same-sex marriage are using the notion of "progress" to help pave the way for legalisation of gay marriage.
Bishop Davies will accuse also Prime Minister David Cameron of attempting to redefine the identity of marriage for "generations to come" without either a mandate from the electorate or properly consulting on the consequences of the proposal.
"This Christmas we are also conscious of new shadows cast by a Government pledged at its election to support the institution of marriage," he will say.
"This vital foundation of society, the 2011 census indicates, now stands at perhaps is lowest ebb.
"At such a moment the Prime Minister has decided without mandate, without any serious consultation to redefine the identity of marriage itself, the foundation of the family for all generations to come.
"This is again done in the name of progress... The British people have reason to ask on this night, 'where is such progress leading?'"
His comments will come hours after David Cameron's Christmas message, which referred directly to his own personal faith, in what was seen as an attempt to heal the rift with the Church.
Cameron said the end of the year was also a time to focus on the Christian message and said he would pray for everyone to have a happy and peaceful time "however you celebrate this time of year".
The Bishop will also use his homily to denounce the "industrial scale" of abortion in British society and destructive experiments on human embryos.
He also will also point out how Christmas and the birth of Jesus cast "a searching light on the darkest shadows of our time".
Bishop Davies will suggest that apparent contempt for human life is connected to the growing loss of respect for the elderly, saying: "The widespread neglect and ill-treatment of the frailest, elderly people in our society: concerns highlighted in the Care Quality Commission's recent report.
"The growing concerns about end of life care and what is happening to the most vulnerable in our hospitals.
"This dark side to our society is surely connected to the discarding of human life from the beginning in legalised abortion on an industrial scale, in reproductive technologies, in embryo experimentation which our laws have sanctioned."
Bishop Davies will tell the congregation they have arrived at a time to "stand up for what is right and true as previous generations have done before us: to give witness to the value and dignity of every human life, to the truth of marriage as the lasting union of man and woman... the foundation of the family."