The Church of England defended its support for traditional marriage after UK Prime Minister David Cameron voiced his support for allowing churches to conduct same-sex marriage ceremonies.
The UK Government is preparing to reveal its response to a consultation with the public on the matter. Parliament will be given a free vote on the issue.
The church, which maintained its opposition to allowing same-sex marriage in a statement on Friday, said there would need to be "an overwhelming mandate from the consultation to move forward with these proposals and make them a legislative priority."
On Friday, Cameron said he did not want gay people "excluded from a great institution" but added he would not force organizations to hold ceremonies in their places of worship.
The Church defended its position on marriage, saying it is for the good of society.
"It is important to be clear that insistence on the traditional understanding of marriage is not knee-jerk resistance to change but is based on a conviction that the consequences of change will not be beneficial for society as a whole," the C of E said in a statement.
"Our concern is for the way the meaning of marriage will change for everyone, gay or straight, if the proposals are enacted. Because we believe that the inherited understanding of marriage contributes a vast amount to the common good, our defence of that understanding is motivated by a concern for the good of all in society."
'Uniqueness' of Marriage Institution
While same-sex relationships "can embody crucial social virtues" and it is "readily understandable" that the Prime Minister can claim he supports same-sex marriage from conservative principles, the church said there was "uniqueness" in the institution.
"[T]he uniqueness of marriage is that it embodies the underlying, objective, distinctiveness of men and women. This distinctiveness and complementarity are seen most explicitly in the biological union of man and woman which potentially brings to the relationship the fruitfulness of procreation," the church said.
"To argue that this is of no social value is to assert that men and women are simply interchangeable individuals. To change the nature of marriage for everyone will be divisive and deliver no obvious legal gains given the rights already conferred by civil partnerships."
Redefining marriage to include same-sex relationships "will entail a dilution in the meaning of marriage for everyone by excluding the fundamental complementarity of men and women from the social and legal definition of marriage.