Bishop Michael McKenna, whose diocese covers more than 100,000 sq. km across the Central West, said moves to change the definition of marriage would impact only secular law rather than Catholic teaching.

”Catholics will be informed by their beliefs in marriage according to their faith and that will lead some to vote no but others might say that this is what I believe as a Catholic but for various reasons vote yes,” he said.

“I think there are different opinions about changing the law on marriage among all people.

“We have a very clear position on what we regard as Christian marriage and this law, nor any law, would not affect that.”

Bishop McKenna said he was more concerned about the possible impacts of an assisted dying bill due to come before the NSW Parliament in September.

Anglican Bishop of Bathurst Ian Palmer said traditional marriage was the “building block of society” and was a “pre-political and pre-religious” institution that should be preserved in its current form.

“I’m not trying to protect it from a Christian perspective because marriage is pre-Christian,” he said.

“Marriage is not something that’s owned by the church or owned by politics.

“Marriage is a coming together of a man and a woman in an exclusive lifelong relationship. The Marriage Act did not originally carry a definition of marriage because there was no argument about it, that the purpose of marriage was to provide a safe place for children and vulnerable people to grow up and be protected.”