When the Church in Wales authorised the blessing of homosexual civil partnerships and marriages, it did so because it had arrived at a crossroads, and after hesitating took one turning rather than another. It made its choice by repudiating the past and putting its faith in the wisdom of our contemporary, very recent and secular culture.

The whole Christian church stands at these crossroads. Some have taken the same turning, and others are hesitating. But it is surprisingly difficult to describe what the issues are and what the consequences may be of the choices.

There are at least three reasons for this. The first is the very powerful current of secular culture; the second is the obscurity of language where words have multiple meanings; and the third is confusion over what the spiritual significance of sex and sexual acts are.

The current of culture has strengthened and become more uncompromising. That in itself is odd, because the secular understanding of homosexuality and the meaning of marriage are not as clear as campaigning organisations want us to believe.

Gore Vidal, the American literary critic and gay activist might be credited for having invented the term 'gay' when he was an influential writer and thinker in the US in the second half of the twentieth century. He did it to protect his homosexual friends whom he thought would be protected by and benefit from a new image.

Yet he refused to accept that people themselves were homosexual or gay. He wanted to talk instead of acts of sexuality but never but people in boxes of categories. He hated the tendency to reduce complex individuals to tribes or types.

In particular he believed, as someone who lived with another man for most of his adult life, people were far too complex and humanity far too rich and multi-layered to be able to reduce our identity down to what kind of people we wanted to have sex with.

He refused to accept that sex, above all other things, was that important in the human experience.

And perhaps that is the issue. Perhaps all this hangs on how important we think sex is. Clearly in our culture it appears to be almost the most important aspect to being a human. But this is historically unusual; perhaps even unique in world history. It's possible to think that such a priority is about as decadent as one could ever become, given the rich vision of what it is to be human in so many ideologies, religions, philosophies and cultures. But we will come back to that.

Nor does everyone accept that one is born with a particular sexual orientation. There is no consensus for that in the LGBTQI+ community. Peter Tatchell, among others, has many times insisted that there is an element of choice to one's sexuality. Science can find no evidence of any biological imperative that determines the direction of sexual attraction.

Many LGBTQI+ people have never supported the campaign for homosexual marriage. They see it as a straight matter which is essentially about providing a societal framework for 'heteros' having children.

So the cultural issues are more open than most people assume given the enormous pressure of cultural propaganda.

The second problem is language. The words we use can be very difficult. Often this is intentional in order to shift public perception. Not least because there is no single homosexual profile. To do justice to the rich rainbow of sexuality, the spectrum has to be divided into impossibly complex variants. Just try a Google search. You may come up with 37 in some schools of thought, or 52 in others.

Then there is the problem of the dissonance between biology and gender that third wave feminism has imposed on us. Let's also leave that to one side for the moment.

One of the great slogans of the campaign for gay marriage has been 'love is love.' But 'love' of course is usually a euphemism for sex, except when it isn't. But it's never clear if we are talking about sex, romance, eroticism, friendship, companionship or something else.

Most Christians know that Greek does much better than English by at least having four different words so you might at least know what you are talking about.

But that carries us perhaps to the core issue that affects which direction we take at the crossroads. What is sex for?

After all, if you remove sex from the argument, you are left with people committing themselves to one another in platonic faithfulness in anything from pairs to large communities. And so far from Christianity having trouble with that, it pioneered it. The best model is the monastery, but there are others of course.

So the value, purpose, function and place of sex is what we are really arguing about.

And here, there is a clear view that both the Bible and the experience of working the Bible out in practice, which we hand on to one another and call tradition, have come to.

The Christian experience is that sex is dangerous, and can cause great damage to the body, captivate the mind and cause significant harm to the soul. The teaching of Christianity (until the last thirty years) is that it can be and must be contained and harnessed within the heterosexual marriage of two opposite sex people. And in that situation its prime purpose is to be used first and almost exclusively for pro-creation, and not for recreation.

Now, one doesn't have to accept this. Indeed the history of the last century in the West is one of trying to undo and refute this. The problem for the Church is whether or not it is swept up in this re-evaluation of sex as recreational. As well as recreational, secular society has become fixated on romantic and erotic desire. In fact it has turned a stage of development in human affection and societal development into an arrested psychological fixation.

So we have two entirely different assessments of sex - secular and Christian. But perhaps the most important thing to do at this stage, is not to argue their merits for the moment, but to recognise the fact that one is Christian and the other is secular. We might also describe the secular culture as 'hedonist' or pluralist, or any number of other labels, but for the moment it is enough to stick with Christian and non-Christian in order to clarify the lines of thought.

The Church has begun to divide under the enormous pressure of progressive secular culture, but it hasn't divided along the lines of saying that the traditional biblical understanding of sex is not what it is, that is Christian. No one denies that. It divides along the lines of saying that the Christian assessment was wrong and needs changing. This has become an epistemological issue.

So, where does authority lie? The Church in Wales, as with the Episcopal Church in the USA, has changed the hierarchy of authority. The Bible and the experience of its application (under the leading of the Holy Spirit as the Church has claimed) is now placed second to human desire and the promotion of romantic eroticism as a universal aspiration.

This is an enormous decision to make of course. And the implications are huge. Once we say that the Bible is effectively mistaken, and additionally that Christian experience for two thousand years is wrong, what authority do we have left in the spiritual life apart from the prioritising of the sexualized aspects of human desire over all other considerations?

We are left with prioritising secular imperatives and our own personal preferences, and where will that lead us?

The answer is obvious. Further and further away from Jesus, whose warnings about sexual desire were stark; from the Father whose will Jesus introduced us to, and from the Holy Spirit who has guided the Christian experience and sculpted holiness in Christians over the millennia.

It may not be an accident that this endorsing of the secular view of the priority and importance of sex and romantic relationships takes place in association with a culture which also attacked the core beliefs of Christianity.

The priorisation of sex outside marriage is partly what has driven the barbaric practice of destroying our own offspring in their hundreds of millions in their mothers' wombs. If nothing else, this might have offered some glimmer of a warning light that we are not handling sex well. The dramatic increase in paedophilia might send similar signals. So might the assault on marriage that divorce has unleashed.

Churches that have chosen the secular route at the crossroads will find themselves deeply caught up in a culture of secularisation which has driven and developed a deeply anti-Christian ethical assault. This too should make churches pause for more thought.

The proponents of making the romantic and erotic our core value may mask the complexities and difficulties that flow from it by talking of 'love' and commitment and faithfulness, joy and satisfaction, but when you examine each one of those claims or aspirations in forensic detail, the narrative that is accepted by a willing public does not match aspiration with achievement. What is achieved is something much more fragile, complex, difficult and ephemeral. But that is another article.

At its simplest, the language of blessing was always kept for an endorsement of people and choices that by virtue of making a priority of self-sacrifice, humility, and obedience meant that God's presence and touch could be invoked and experienced.

But the secular endorsement of sex and romance makes no pretense at self-sacrifice, humility or obedience. It rather gives itself away by choosing 'pride' as its leitmotif. And so it is difficult to know on what basis churches can offer 'blessing'?

They can certainly offer an endorsement of this new secularization, but they should give far more thought as to whether this constitutes a 'blessing'. There is no record of holiness or Christian heroism or virtue connected with this path that prioritises sexual and romantic satisfaction.

There are plenty of theological and philosophical reasons for questioning the vigourous secular assumption that sex is harmless, good for us and a human priority. Freud may have insisted on this as a theory, but most of Freud's theories have been deeply discredited. The Christian view is that it is powerful and potentially dangerous, addictive and to be firmly kept from becoming a priority.

If the Christian view is right, then we join Gore Vidal in asserting we have no 'sexual identity'. The Christian cannot be described as straight, gay, or any one of 52 further variants. St Paul is crystal clear about this in Galatians 3. Christians carry no adjectives. We are simply baptised believers who surrender all our appetites, needs and ambitions to Jesus for reconfiguration by the Holy Spirit, on His terms not ours.

We understand that the people we live amongst may be deeply attracted and even addicted to sex, and we want to tell them that the Christian way leads to a deeper freedom and a more profound satisfaction of the soul than sex and romance can give to body, mind or heart.

What the Church cannot do is to bless their secular analysis and longings in the name of the God who points us in a different direction at these crossroads.

The Church is indeed divided. But the division is not between old and new, but between a secularised sub-Christianity that prioritises sex, romance and the human appetite, and an orthodox Christianity contoured by the Bible, tradition and the Holy Spirit rather than a secular spirit.

Dr Gavin Ashenden is a former chaplain to the Queen. He blogs at Ashenden.org