In the wake of the Irish referendum in May and the decision of the US Supreme Court in Obergefell v. Hodges, same-sex marriage proponents in Australia have the winds of change at their backs and are ramping up legal and moral pressure on their traditionalist opponents.

Most recently, Australian Marriage Equality national director Rodney Croome has condemned the Roman Catholic Archdiocese of Tasmania and its bishop, Julian Porteous, for having sent out copies of the booklet Don’t Mess With Marriage through Catholic schools in Tasmania. Pupils received the booklet in a sealed envelope to take home to parents.

Croome wants to take Archbishop Porteous to the Tasmanian anti-discrimination commissioner for having dared to send out a document containing Catholic teaching to Catholic parents via their children who are Catholic pupils in Catholic schools. Croome claims the letter denigrates and demeans same-sex relationships. In reality, it is Croome himself who denigrates and demeans his opponents.

Don’t Mess With Marriage – actually a pastoral letter from the Catholic bishops of Australia – sets out explicitly to defend the traditional Christian meaning of marriage and to rebut the arguments of same-sex marriage proponents. The bishops say they want to engage with the debate about the meaning of marriage, to explain the church’s teaching on marriage, and to emphasise the importance of ‘every man, woman and child…[being treated] with respect, sensitivity, and love.’

There is little there that coincides with the views of Croome and co. Oddly, Croome says it’s fine for the church to teach what it likes from the pulpit (as if there are no young people in Catholic churches), but by opting for a cheaper distribution service than that offered by Australia Post, Catholic schools have turned their students into ‘couriers of prejudice’.

The debate on same-sex marriage has evolved very rapidly in most western countries over recent decades. Cultures change, and values change with them. Greater acceptance of homosexuality has led to amendments to the criminal law, to widespread distaste for discriminatory behavior, and to taboos being eased — allowing gay and lesbian people now to be confident and comfortable in public life.

Even many Christian churches are changing. The Uniting Church long ago voted to admit homosexuals as clergy. There are now gay and lesbian bishops, priests and deacons openly holding office. While acceptance of homosexuality is by no means universal in the Anglican Church, the cultural and theological changes that have taken place are probably, and rightly, irreversible.

It’s likely that at some point soon Australia will follow overseas trends and change the law to permit same-sex marriage. Since 2014, they have been allowed to marry in the UK (except in Northern Ireland). The recent slender majority decision from the US Supreme Court didn’t so much legalize same-sex marriage as actually compel states to issue marriage licences to same-sex couples. But a significant note of caution was sounded.

The four dissenting judgements in Obergefell v. Hodges, led by that of Chief Justice John Roberts, were not concerned with whether or not same-sex marriage is a good idea. The justices dissented because the process was wrong: it was unconstitutional, they held, for the court to usurp the right of the people, through their elected representatives, to make a decision about marriage. Judges are there only to resolve disputes about law.

Roberts, who expresses nothing but goodwill towards those who will celebrate the Supreme Court’s decision to expand the meaning of marriage, nonetheless said that the proponents of same-sex marriage have lost ‘the opportunity to win the true acceptance that comes from persuading their fellow citizens of the justice of their cause. And they lose this just when the winds of change were freshening at their backs.’ To those who claim victory, he urges against gratuitous assaults on the views of those who have long held to the traditional meaning of marriage and to avoid portraying ‘everyone who does not share the majority’s “better informed understanding” as bigoted.’

According to a recent poll, 70 per cent of Australians agree that excluding same-sex couples from marriage fosters discrimination. Whether or not the matter is resolved by the Abbott government, ultimately it will be for the Australian people, through their elected representatives in the Parliament, to decide the scope of marriage. Traducing those with an opposing point of view will introduce bitterness and anger to the healthy debate currently under way in Australia, and threatens to provoke a culture war which could leave a lasting wound. After all, Australian Marriage Equality has still to win over the hearts of 30 per cent of the population, many of whom base their opposition to same-sex marriage on sincerely held religious beliefs.

Croome and other advocates, such as Sydney lawyer Tim Dick, regularly claim to be respectful of religious freedom. Writing in the Age last week, Dick said that the campaign for same-sex marriage is ‘a fight for true religious freedom: the freedom from other people’s dogma telling us who we can marry and who we can’t.’ But the freedom he has in mind bears no relation to the definitions of religious freedom set out in the UN Universal Declaration of Human Rights 1948 or the International Covenant on Civil and Political Rights 1966, which uphold the right of the individual to manifest his or her beliefs. The freedom Dick is defending is not freedom for religion, but freedom from religion.

In secular Australian society there ought to be no place for any religion to dictate the scope of the civil law of marriage. Religious marriage is quite distinct from civil marriage, and religious groups must continue to enjoy the freedom to define marriage in accordance with their own traditions, as the NSW Presbyterian Church is proposing to do by withdrawing altogether from any amended Marriage Act. At the same time, it is both unjust and illiberal for those advocating change to the civil law to attempt to compel religious believers to endorse forms of marriage that contravene the tenets of their faith. The answer, as Human Rights Commissioner Tim Wilson has argued, is to separate civil and religious traditions but treat them equally in law.

By denouncing those with whom he disagrees as prejudiced denigrators, Rodney Croome is giving the lie to the very values of justice, equality, and inclusiveness for which he professes to stand.