According to Odgers’ Australian Senate Practice — the authority on the upper house’s powers, procedures and practices — it is unparliamentary to refer to a senator’s religion.

This, however, did not stop Brisbane-based Greens senator Larissa Waters engaging in a bout of anti-Catholic sectarianism at Senate question time last Monday. She asked Senator George Brandis, who represents the Prime Minister in the upper house, a question on climate change — following the release of Pope Francis’s encyclical Laudato Si’. The English title for the encyclical is On Care for our Common Home .

Initially Waters declared that Laudato Si’ “calls for an urgent moral response to the scientific ­reality of global warming, rampant environmental destruction and ­extreme poverty and condemns ­indifference, denialism and ­obstructionism”.

The Greens senator then threw the switch to sectarianism when she made the following statement: “42 per cent of the Abbott cabinet is Catholic, including the Prime Minister himself who, of course, once trained to be a Catholic priest”.

This commenced over five minutes of dispute during which the President of the Senate, Stephen Parry, ruled part of the question out of order.

Brandis’s reply was direct. Namely that the Coalition “will be setting our priorities and making our policy decisions in accordance with science and good public policy, not in accordance with theology”.

Earlier, Waters had suggested that Tony Abbott “should listen to the leader of his own church and abandon attacks on the clean energy target”. So, according to ­Waters, ­Abbott should follow the teachings of Pope Francis on what Laudato Si’calls global warming because he is not only a Catholic, but a person who spent some time as a semin­arian training to be a priest. ­Waters seems completely ignorant of Catholic theology.

As Professor John Warhurst wrote in his Canberra Times article on Wednesday: “Those who imply that Catholic political leaders ­usually follow edicts from the Pope just don’t understand the enormous variety of beliefs within Catholicism.”

Warhurst added: “The policy differences between Abbott, Joe Hockey, Malcolm Turnbull and Kevin Andrews, for instance, are enormous and this reflects the diversity within Australian Catholicism. Outside the cabinet there are many other Catholics whose views show even greater diversity than among cabinet ministers, not to mention those Catholics in other parties”.

Australian Catholicism aside, the popes have never claimed that the faithful should be bound by the teachings of the church other than with respect to faith and morals.

The church’s social teachings go back at least as Leo XIII’s ­encyclical Rerum Novarum in 1891, which upheld the concept of a just wage. A similar teaching was expounded 40 years later by Pius XI in Quadra­gesimo Anno and by John Paul II’s 1991 encyclical Centesimus Annus.

Some Catholics choose to follow the teachings of the church on social and economic policy. Other do not, nor are they expected to. Likewise concerning science. This is acknowledged in Section 188 of Laudato Si’, where the Pope writes that “the Church does not presume to settle scientific questions or to replace politics”.

Catholics are only expected to follow the church’s teachings concerning faith and morals. Even in this area, the Pope rarely claims infallibility. The last occasion where the Pope spoke “ex-cathedra”, binding all the faithful on a matter of faith and morals, occurred in 1950. This took the form of what was termed an apostolic constitution — or papal bull — and defined the doctrine of the assumption of the Blessed Virgin (Jesus’s mother). Hardly a matter to interest Waters.

Waters believes that because Abbott is a Catholic, he should abide by Laudato Si’. This suggests that she has not read the full document. According to the encyclical, “concern for the protection of ­nature is incompatible with the justification of abortion” (Section 120). Moreover, Francis restates the Catholic Church’s opposition to artificial contraception (Section 50). Not much for Waters to cheer for here. Also there is the fact that the Church opposes same-sex marriage.

And there’s more. Towards the end of the encyclical, Francis urges the faithful to “stop and give thanks to God before and after meals” (Section 227).

Also he wants us all to participate “in the Eucharist” on Sundays (Section 237). All this might seem familiar to pre-Vatican II Catholics. Attend Mass on Sundays and say grace before and after meals. But this is unlikely to be a hit with the Greens.

Waters and her colleagues should not even be pleased with the Pope’s prescription to counter global warming. The Greens deputy leader believes that ­Francis has views on the Abbott government’s clean energy target. Possible — but unlikely. However, she seems unaware that Laudato Si’ opposes a carbon tax or an emissions trading scheme (Section 171). Fancy that.

Waters is not the only one exhibiting an invincible misinterpretation of the teaching authority of the Church. Soon after Laudato Si’ was released in Australia, ABC-TV’sThe Drum (June 19) put on one of those all-too-familiar ABC discussions where everyone agrees with everyone else in a left-of-­centre kind of way.

In this instance, journalist Tori Shepherd agreed with John Hewson, who agreed with fellow panellist Bruce Haig, who agreed with presenter John Barron, that we all should follow Francis’s teachings on climate change.

The highlight of the so-called “debate” occurred when Hewson stated that, according to the Pope, “it’s a sin to be a climate denier” and Barron responded “right”. No — wrong. And this howler from Barron, who fronts the taxpayer-funded public broadcaster’s fact-checking unit.

Meanwhile, The Age in Melbourne has been publishing piece after piece in its printed edition urging readers to follow the encyclical.

It seems that The Age’s editor is blissfully unaware that the Pope has urged the faithful to avoid “the use of plastic and paper” (Section 211).

If implemented, the recommendations of Laudato Si’ would adversely affect the poor in both developing and developed nations, due to higher energy prices. That’s why it makes sense for Australian politicians, Catholic and non-Catholic alike, not to regardLaudato Si’ as in any sense infallible.