If Mr. Folau begins a legal case, it would most likely be over whether employers imposing values on employees is an undue burden on the freedom of religious expression, said Gillian Triggs, a lawyer and former president of the Australian Human Rights Commission.

Two years ago, Australia was in the throes of a fierce debate about whether gay people should have the right to marry. Same-sex marriage was eventually legalized in December 2017, with a majority of Australians voting “yes” in a public opinion survey. But religious dissenters put up a fight, arguing that it would impinge on freedom of religious expression.

Australia is “manifestly and demonstrably behind” in human rights compared to the United States and Europe, Professor Triggs said. But the country doesn’t have an official human rights charter, and many of its protections, if not officially legislated, are implied, she added.

While some laws make it illegal to discriminate on the basis of gender or sexual orientation, there are no federal protections against public vilification on the grounds of sexual orientation.

Half of the population identifies as Christian, according to the latest census, but secularism is on the rise. In the survey on same-sex marriage, nearly 40 percent of Australians who voted — 79.5 percent of the population — were against it. One poll found that Australia is less inclusive of lesbian, gay, bisexual and transgender people than countries like France and Canada, although it scored higher than the global average.