The Church of England have today issued their formal response to the government’s consultation on same-sex marriage. They had a great opportunity to acknowledge the diversity of views within their own ranks and to move on from the defensive tone that characterises so many Christian contributions to debates over sexuality.

It is an opportunity that they have completely missed.

There is very little sign of originality or creative thinking in the CofE’s statement. It relies heavily on old, and largely discredited, arguments, to push its opposition to government plans to allow legally recognised civil marriage ceremonies in England and Wales.

The CofE’s central argument is the same one used by most other opponents of marriage equality – and it is equally unconvincing. This is the claim that the government is “redefining” marriage, which has been “always and exclusively between a man and a woman”.

Marriage has meant many different things in many different cultures. Very few British Christians would now argue for arranged marriage, let alone forced marriage or marriage while still of childhood age. Yet all these practices have been normal for Christians in certain times and places. When the Married Women’s Property Act was passed in 1882, critics claimed that it was an attack on the sanctity of marriage. Similar claims were made when laws were introduced to protect women from domestic violence and rape (indeed, Stephen Green of the right-wing fundamentalist group Christian Voice still claims that marriage has been undermined by the law that bans men from raping their wives). As a friend of mine put it more bluntly recently, “The fact that you can’t sell your daughter for three goats and a cow suggests that we have already redefined marriage”.

The reality is that on many occasions marriage has been about money. As David Graeber points out in his recent history of money and debt, this has worked in several ways. “Brideprice” has involved a man making a payment to his new wife’s father. The opposite system is that of dowries in which the father makes a payment to the groom. In the UK today, money-based approaches to marriage are still strong. They are preserved symbolically in the appalling practice of the bride being “given away”. More alarmingly, they are very visible through the hugely profitable wedding industry. The average cost of a wedding in the UK is now roughly equivalent to the average annual income.

Thankfully, marriage has never been solely about money. Jesus shocked his listeners with his comments on marriage. In a time when only men could initiate divorce – often throwing their wives into social disgrace and even poverty – he criticised casual divorce. In a culture that blamed women for giving men lustful thoughts, he encouraged people to take responsibility for how they dealt with their own thoughts, and be aware of what they did in their hearts.

In other words, Jesus challenged relationships based on power and money in favour of relationships based on love, equality and self-control. It might be said that he redefined marriage.

The second major argument in today’s statement is the claim that men and women are fundamentally different. It speaks of the “biological complentarity” of men and women. Marriage, it argues, “embodies the… distinctiveness of men and women”. It states, “To argue that this [difference] is of no social value is to assert that men and women are simply interchangeable individuals”.

The Church of England leadership do not seem to have noticed the reality, diversity and uniqueness of the human beings they are called to serve. Of course, the writers of this document may well have major problems with transgender and genderqueer people. Disgracefully, the document doesn’t even mention the government’s proposal to scrap the outrageous practice by which a married person who transitions gender automatically has their marriage dissolved. But no-one can deny the reality of intersex people – those who are born without a clearly identifiable biological sex. This includes people whose genitalia do not “fit” with social categories, as well as those whose chromosomes do not “match” their genitals. About one in every 2,500 people are born intersex. Has the Church of England nothing to say about them, let alone to them?

As the theologian Susannah Cornwall points out, the significance of intersex goes beyond its statistical frequency. It disrupts any attempt to fit men and women into simplistic binary categories.

In the past, people argued against mixed-race marriage on the grounds that people of different races are fundamentally different. The vast majority of people in this country would now find such a claim to be morally and intellectually abhorrent. I hope the time will come when we are just as appalled when the claim is applied to people of different genders.

The CofE’s statement includes more scaremongering about the possibility of churches facing legal action for not carrying out same-sex weddings. This is extremely unlikely (not least because almost everyone campaigning for marriage equality respects the right of faith groups to make their own decisions on it). Further, it is only an issue because the Church of England is an established church. This position gives it both privileges and legal responsibilities. If top Anglicans want to have more freedoms, they need to give up their privileges.

Nonetheless, I’m more than ready to agree that one the CofE have a point in one aspect of their response. They suggest that the government’s plans, and the discussion around them, have given the impression that the law recognises two forms of marriage, “civil” and “religious”. In reality, this refers only to a type of ceremony, not to the legal status of the relationship.

Unfortunately, the CofE’s statement does not offer a solution to this confusion other than to try to keep things as they are. But marriage laws are already complicated, confusing and easily misunderstood. It is not proposals for same-sex marriage that are mixing things up. Not only do same-sex couples have different legal rights to mixed-sex couples, but different religious groups have different entitlements when it comes to the authority to perform legally recognised weddings. For example, the law that allows Quakers to carry out their own weddings dates back to the Marriage Act of 1753. It has barely been updated since. The Quakers are one of the groups now seeking the right to carry out same-sex marriages. The government plans to deny them this right, which they will restrict to civil ceremonies, thus making the system even more complicated and discriminatory.

To deal with all this, we need a thorough overhaul of marriage law to recognise the diversity of beliefs and relationships in a plural society. A government consultation aimed at such an overhaul would be a courageous and welcome step indeed.

At the Ekklesia thinktank, we have long argued that celebrating marriage and making commitments should be separated from the (arguably less important) process of gaining legal recognition. This would mean that people could carry out ceremonies with personal, social and – if important to them – religious significance, with legal registration being a separate process. This would allow supporters and opponents of same-sex marriage to act on their beliefs, to promote them, to publicise them and to seek to persuade others, without being able to use the law to enforce their views on those who disagree.

The CofE’s statement makes the frankly offensive claim that “almost all other churches” regard marriage as a union of a man and a woman. It might have been more accurate to say “most”. In the UK, churches that recognise same-sex marriage now include the Metropolitan Community Church, the Religious Society of Friends (Quakers) and the General Assembly of Unitarian and Free Christian Churches. The United Reformed Church will be discussing the issue at their General Assembly next month. There are calls amongst Baptists for each church and minister to be allowed to make up their own mind on the subject. There is significant support for same-sex marriage within the Methodist Church, the Church of Scotland and indeed within the Church of England itself, as well as from smaller numbers in the Roman Catholic and Orthodox Churches.

The statement makes no acknowledgement of the range of views within the Church of England’s own ranks. In talking about what “churches” believe, rather than what Christians believe, it seeks to uphold the authority of a privileged establishment, rather than to recognise the Holy Spirit’s movements amongst millions of believers – and unbelievers. While some church leaders are determined to resist change, other Christians seek, however imperfectly, to be at the forefront of it. Thankfully, we don’t need to rely on hierarchies. In the Church as well as in society, change comes from below, not from above.