A survey of ordinary believers' views on sexual ethics signals a potentially ground-breaking change of emphasis for the Roman Catholic Church.
Roman Catholics have been more used to receiving guidance from the Vatican than giving it.
But with Pope Francis has come a growing sense that he intends fundamental change in the way his huge Church is run - and that he wants to include "ordinary" Catholics in it.
His unprecedented exercise in consultation - the survey sent to all Catholic bishops with instructions to consult as widely as possible - is a powerful further sign of reform in the old top-down way of governing the Church.
The survey's 39 questions deal with sensitive subjects - contraception, gay marriage, sex outside marriage, and whether divorced and remarried people should be allowed Holy Communion.
Diverging from doctrine
The Roman Catholic Church in England and Wales was the first in the world to put the survey online, and is encouraging all Catholics to complete it by the deadline on 20 December.
Their responses are likely to confirm what bishops already know - that the behaviour of Catholics, including the roughly one third who go regularly to church, is diverging dramatically from the model of Catholic practice set out by the Church.
But rather than criticise, Pope Francis is convinced that the Church needs to understand - and his survey is part of that effort.
A few weeks ago, the Pope criticised the Roman Catholic Church for being too focused on enforcing the rules for human behaviour based on its traditional beliefs.
He called it being locked up in "small things and small-minded rules", and an obsession with "the transmission of a disjointed multitude of doctrines".
There is no sign that Pope Francis plans a major overhaul of Church doctrine, but it is clear that he wants a switch in emphasis to a message of mercy and forgiveness, especially towards those who are suffering.
The survey is itself a tacit acknowledgement that the way the Church deals with Catholics who cannot - or will not - follow official church teaching must change.
The way the survey has been worded has been criticised as obscure and convoluted, but there is no denying that it goes to the heart of fundamental and often awkward issues in the way Catholics lead their lives.
In one section - headed "On Unions of Persons of the Same Sex", one question asks: "What pastoral attention can be given to people who have chosen to live in other types of union?"
Another addresses the issue of contraception - but instead of using that word it refers to "The openness of the married couple to life".
The Church rules out artificial contraception, but questions whether couples are "aware of how morally to evaluate the different methods of family planning", before asking more directly "Is this moral teaching accepted?"
The truth is that much of the Church's moral teaching is not accepted.
Professor Linda Woodhead of Lancaster University, in research among 1,672 British Catholics for the Westminster Faith Debates, finds them largely holding on to their identity as Catholics, but more likely to trust their own reason and judgement than the Church's rules in deciding their moral behaviour.
On an issue by issue basis, the results are remarkable, and give an insight into what the Pope is likely to learn from his survey.
According to Professor Woodhead's findings, four in ten churchgoers - who are more respectful of the Church's teaching than non-attenders - would ban abortion altogether, and just under half of churchgoers think same-sex marriage is wrong.
She says: "If we measure ['faithful Catholics'] by the criteria of weekly churchgoing, certain belief in God, taking authority from religious sources, and opposition to abortion, same-sex marriage and euthanasia, only 5% of Catholics fit the mould, and only 2% of those under 30".
Those figures exclude elements such as the teaching on contraception, widely ignored by Catholic lay people.
Pope Francis is not offering to change teaching on contraception.
The Church would not believe it was serving anyone by dismantling its values - diluting what it regards as a "gold standard" for people who want to lead a good life.
Like the Church's understanding of what constitutes a "valid" marriage - that is, between a man and a woman - contraception is an issue of doctrine, or core belief, and not open to reform.
But that is not to say there is not considerable room for manoeuvre, allowing the change of focus to the "kinder" and non-judgmental approach Pope Francis has repeatedly called for.
The Pope has shown that he is aware that even those Roman Catholics who shun the rules are hurt by the way the Church deals with them, in deeds as well as words.
For example, in the past the Church has described "deep-seated homosexual tendencies" as "objectively disordered".
Pope Francis has said that he does not feel in a position to judge homosexual people.
Then there are the divorced people who have remarried - and are, according to the strict interpretation, therefore committing adultery and are denied Holy Communion.
The Vatican document accompanying the survey hints at a realisation that all might not be well by pointing out mournfully that "many Catholic children and young people will never see their parents receive the sacraments".
Even Catholic bishops thought of as traditionalist - such as the Bishop of Portsmouth, Philip Egan - have called for a more merciful way of dealing with such people.
Even without a reform of core beliefs, there could be significant changes in practice and what has already been identified as Pope Francis's "style" to reduce conflict in the Church's ideal values and the real lives of its members.
As some in the Church have already pointed out, to a great extent "style is substance" when it comes to applying the rules.
In matters such as contraception for example, new thinking could call for Catholic couples to be "open to life" in their sexual relationship, but leave up to their consciences how exactly they manage it.
Responses to the survey are to be given to Catholic bishops before they gather in Rome next September for a special meeting, or synod, to discuss the Church's approach to "the family".
They are due to meet in 2015 to issue new guidance to Catholics based on their discussion next September.
Most were selected by the traditionalist popes John Paul II and Benedict XVI, but the Catholic commentator John Wilkins says even traditionalists are aware of the gulf between teaching and practice.
"It's a dangerous gap for an institution like the Church," says Mr Wilkins. "It can deal with it in two ways - either by clamping down from the top, which runs the risk of reducing the Church to a small sect, or by adapting its teaching, focusing on Jesus, so that Catholics can say, 'yes, that's me, that's what I believe'."
To some extent the very fact of the Pope's survey, broaching issues Catholics were once not encouraged to discuss, has raised expectations, assumptions which, whether justified or not, might be hard to satisfy.