The Commons voted by a substantial majority in support of allowing gay marriage on 5 February. I am glad that over 130 Conservative colleagues voted for the bill and I understand why some did not, given the outright hostility to the measure among some groups in society who are over represented (statistically speaking) among Conservative Party membership.

If this bill becomes law, as I expect it will, then the UK joins many other countries that recognise same sex relationships in marriage. Same sex marriage was first legalised in the Netherlands twelve years ago. Since then it has become legal in Spain, Denmark, Argentina, Mexico City, New Zealand, Canada, South Africa and last year, for the first time in America, three states voted in public plebiscites to join the other six states and Washington DC that have legalised same sex marriage.

President Obama has declared his support, and there is no doubt that the Republican Party's result in last year's election was heavily influenced by its attachment to a right wing socially conservative agenda. France is at the same stage as the UK, with a bill going through the legislature amidst some opposition and protest. Despite the barbarism that exists still in parts of Africa, the Middle East and Asia, the trend toward giving single sex couples full marriage rights is gaining momentum.

Every independent opinion poll shows a majority of the public in support of the change. The YouGov poll for the Sunday Times found that 55% support reform and 36% are opposed. An ICM poll for the Guardian found 62% in favour with 31% opposed. But what these headline numbers don't show is the differential in support by age. People over the age of sixty five are opposed in far greater numbers than younger people. Only a minority of over sixty five year olds support the case for change; all other age groups are supportive of the bill and the younger the age group the stronger the support. The demographics of Conservative Party membership are heavily skewed to the over sixty five year old cohort which explains, in part, why my colleagues faced such huge local opposition and pressure.

The other reason why so many older Conservative supporters are against the bill is that they think the government is going to force Churches to marry same sex couples. They think that because that is the impression created by The Coalition for Marriage and some Churches.

The Coalition for Marriage, and other evangelical groups, has operated in an extreme and ruthless manner. They spent all of last year orchestrating as many hostile responses to the consultation document as possible, and the primary means by which they whipped up such vocal opposition was through a deliberate misrepresentation of the government's intentions. The scaremongering that went on was underpinned throughout by the lie that the government was going to force religious bodies to conduct same sex marriages on religious premises. Somewhat naively I expect churches and other religious institutions to aspire to the truth in their dealings and public pronouncements; in this I was sorely disappointed.

I am opposed to any obligation being placed on religious organisations to marry people of the same sex. But by setting up this straw man the Coalition for Marriage, the Catholic Church, and even, I very much regret, the Church of England who should have known better, were able to drum up a great deal of support among people who feel very strongly that marriage in church should remain between a man and a woman. Last weekend the Church of England admitted finally that it was not "realistic or likely that Churches would be forced to conduct same sex wedding"; what the Attorney General and supporters of the bill have said all along. But the lies and smears have served their purpose and, as evidenced by my colleague's postbags, most people assume that what is proposed are weddings in church for same sex couples.

What the bill is about of course is civil marriage. The claim that marriage is being redefined is wrong on many counts; the argument pre-supposes that marriage has been intrinsic to religion in an unaltered state since its origins. But that is not the case. Some heterosexual couples have declined to marry because they view marriage as an inherently patriarchal institution. In Medieval times marriage was an economic relationship and was used by men to secure their estates by ensuring that property was passed down to their legitimate, male, heir.

Conor McCarthy argues in his study of Law, Literature and Practice in respect of Marriage in Medieval England that "marriage in secular law contrasted with the ecclesiastical view of marriage in many respects. The two approaches to marriage coexisted; the Church, by and large did not interfere in secular matters relating to marriage, and the secular jurisdiction left spiritual matters to the ecclesiastical courts. The two jurisdictions had very different notions of the purpose of marriage, contradictory notions even but these contradictory notions coexisted".

The bill we are debating seeks to reform and extend marriage that is within the secular jurisdiction. The church does NOT have a monopoly over the state of marriage, it never has had and I urge my honourable friends not to give in to the unseemly and wholly inappropriate pressure that has been applied by some churches as they have crossed the line into what is the preserve of the state and secular power.

One thing that has been overlooked in this debate has been the point that gay people have always been able to marry of course. That is, as long as we have chosen someone of the opposite sex. In Hollywood such arrangements were known as lavender marriages and served to ensure that male stars had cover from the sort of rumours that would ruin their box office appeal and earnings. Far less glamorous but no less significant were marriages entered in to by male politicians of all parties who wanted to stand for Parliament, after a certain age the only way to silence career limiting questions would be to marry. Sometimes of course such marriages took place in good faith and in the strong hope that people's innate homosexuality could be suppressed and a quote "normal life" could be pursued.

Now we are asking for the right to marry each other in an open, truthful and committed sense. A clean break with the lies that necessitated our survival in years gone by. There will be many people for whom civil partnerships were and are the answer. But there are same sex couples who want to marry and I am particularly thinking of younger people who cannot understand why they shouldn't have the same opportunities to marry as everybody else.

It is vital that the concerns of opponents to the bill are addressed. Tolerance and respect need to work both ways. One issue that I think will be reinforced in the committee stage of the bill is the protection of teachers and schools. Also, the vast majority of gay people are prepared to accept that churches should not have to conduct single sex marriages, if it is against their beliefs. One day I hope that will change and it is encouraging to hear that the Quakers, the Unitarians and the Reform Jews are keen to hold ceremonies for weddings as they do at the moment for civil partnerships. But not all change can come at once and just as it is up to the state to arbitrate on secular and civil matters so it is the domain of the church to rule in spiritual matters. This bill protects both sides and now has the backing of the House of Commons, a huge step forward in the right direction.

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