Legalising gay marriage could lead to the Church of England's disestablishment, it has warned.
Its response to the coalition's consultation on proposals to allow same-sex couples to marry in the same way as heterosexual couples attacks ministers for pursuing the reform "for essentially ideological reasons" and concludes doing so would be "deeply unwise".
Under the government's proposals no religious organisation would be forced to conduct a same-sex marriage. The coalition says it will "make no changes to religious marriages".
The Church of England disagrees. It said "disingenuous" ministers are confusing the wedding, which can be either civil or religious, with the institution of marriage itself.
"Such a change would alter the intrinsic nature of marriage as the union of a man and a woman, as enshrined in human institutions throughout history," it argues in its submission to the government's consultation.
"Marriage benefits society in many ways, not only by promoting mutuality and fidelity, but also by acknowledging an underlying biological complementarity which includes, for many, the possibility of procreation.
"The law should not seek to define away the underlying, objective, distinctiveness of men and women."
The Church of England, which 'solemnizes' one-quarter of marriages which take place in England, warned that redefining marriage to create a "statutory" institution would have serious implications for the position of its own institution.
It warned the changes "will potentially have a very significant impact on our ability to serve the people of the nation as we always have done".
Anglican resistance to the coalition's gay marriage proposals comes after even more outspoken resistance from Britain's leading Roman Catholic figures. The reforms were condemned as "grotesque" and "madness" by Cardinal Keith O'Brien in March.
Despite this Liberal Democrat equalities minister Lynne Featherstone offered a "cast-iron guarantee" that gay marriage would become a reality by the 2015 general election.
"The essential question is not whether we are going to introduce same-sex civil marriage but how," she was quoted as saying by the Telegraph newspaper.
Her confidence does not reflect serious levels of opposition to the move among many Conservative MPs, however.
Last month saw Downing Street concede the issue would not be whipped when presented to the Commons, after ministers including Northern Ireland secretary Owen Paterson and defence secretary Philip Hammond made their views clear. A free vote allows Cabinet ministers to oppose the proposals.