The Church of England has "nothing to fear" from the introduction of gay marriage, according to a group of senior bishops and clergymen.
The influential Anglicans said the prospect of same-sex marriage should be a "cause for rejoicing" and argued the perception that the majority of the Christian Church opposed legalising it was wrong.
In a letter to the Times, the signatories said: "Recent statements by church leaders past and present may have given the impression that the Church is universally opposed to the extension of civil marriage to same-sex couples. We believe that does not adequately reflect the range of opinion which exists within the Church of England."
The signatories - including members of the General Synod, the governing body, and high-ranking clergy - describe marriage as a "robust institution which has adapted much over the centuries" and say it has "moved beyond the polygamy of the Old Testament and preoccupation with social status and property in pre-Enlightened times".
Arguing that "God's grace" is at work in same-sex partnerships, the letter adds: "The Church calls marriage holy or sacramental because the covenant relationship of committed, faithful love between the couple reflects the covenanted love and commitment between God and his church. Growing in this kind of love means we are growing in the image of God. That there are same-sex couples who want to embrace marriage should be a cause for rejoicing in the Christian Church."
The joint statement is said to have been organised by Dr Jeffrey John, the openly gay Dean of St Albans.
"We believe that the church of England has nothing to fear from the introduction of civil marriage for same-sex couples," the letter adds. "It will be for the churches to then decide how they respond pastorally to such a change in the law."
Plans to legalise gay civil marriage by 2015 have been put out for consultation by the government.
Under the proposals same-sex couples will be entitled to get married in a register office or other civil ceremonies, or convert existing civil partnerships.
Existing marriages in which one partner changed their sex would also no longer have to be ended.
The blueprint, however, maintains a legal ban on same-sex religious services despite some churches expressing an interest in conducting them.
Leaders of the Roman Catholic Church have remained resolutely opposed to gay marriage and blessing civil partnerships but the issue has split the Anglican Communion.