Leading members of two more religious denominations have joined the attack on Government proposals to allow same-sex couples to marry.
A Sikh peer and a senior rabbi added their voices to protests by Anglican and Catholic bishops against the Coalition’s plans to allow homosexuals to marry.
Lord Singh, head of the Network of Sikh Organisations, and Rabbi Yitzchak Schochet, who advises the Chief Rabbi on family issues, accused the Coalition of launching an “assault” on religious values.
Their intervention came as Reg Bailey, David Cameron’s adviser on family issues, said the reforms risk leading to polygamy and even marriage between siblings.
Lord Singh said the plans would “dilute” the definition of marriage in religious scriptures. He told The Sunday Telegraph he would vote against the legislation in the Lords.
He said: “It’s being changed and for no real gain because the law rightly gives every respect to a civil partnership. It is more of a sideways assault on religion, that 'we can dilute your beliefs and values’, and I find that concerning.”
Lord Singh, who represented British Sikhs at the wedding of the Duke and Duchess of Cambridge, said Sikh scriptures do not condemn homosexuality and encourage Sikhs to respect “all ways of life”. But added: “In the pursuit of equality one shouldn’t dilute and distort another’s beliefs.”
Rabbi Schochet described the proposals as “pure politics” and an assault on “traditional values”, adding it was hypocritical to impose such a far-reaching “secular” change when religious leaders would be condemned for imposing their values on others.
Rabbi Schochet, who was considered a front runner to become the next chief rabbi but pulled out of the race last week, said: “The hallmark of Judaism is the family. The traditional family – a husband, a wife and children.
“Ultimately, of course, it’s not for me to dictate to government and start telling them what to do, I can just simply decry what is going on the basis of what I consider to be, from a religious biblical perspective, an assault on religious values.”
Rabbi Schochet, the minister at Mill Hill synagogue in north London, added that he welcomed homosexual Jews into his synagogue but said redefining marriage to accommodate same-sex couples would “run counter to the fundamentals of our beliefs”.
His views are contrary to those of the British Jewry’s Reform and Liberal movements, which have both backed same-sex marriage.
Mr Bailey, the head of the Mothers’ Union, said: “If you say it can be two men and two women, why can it not be a man and two women or a man and three women?”
He added that others may seek to contest the minimum age of marriage or even call for two brothers to be allowed to marry.
The Government last week launched its consultation document, asking the public if they “agree” or “disagree” with the proposals. But the document said ministers were looking at how, rather than if, the ban should be lifted.
Under the proposals same-sex couples would be allowed to marry in register offices and venues such as hotels, but not in churches, synagogues and other religious premises.
Ministers argue that the change will therefore affect “civil” rather than “religious” marriage, although opponents say it cannot be split.