CATHOLIC Diocese of Toowoomba Bishop Robert McGuckin says the church can support the notion of same-sex unions, not marriage.
Bishop McGuckin said the law should not be allowed to change the Biblical definition of marriage, which he explained was the union between a man and a woman for the procreation of children.
The term union should instead be used, Bishop McGuckin said.
"By all means you may give recognition to other forms of relationships but once you start calling that marriage, you reduce what marriage is," he said.
"Marriage is the union between a man and a woman, for the good of the spouses and for the procreation and the good and the upbringing of children."
He said the Catholic Church did not deny same-sex relationships existed, and it did not set out to deny them civil and lawful rights.
"You don't want to be denying people the ability to choose (relationships). If they choose a same-sex relationship then that's fine but when you start to move it into calling it marriage, that's where we would see the difficulty," he said.
Bishop McGuckin said television shows such as Married at First Sight, which televises the marriage of a man and a woman meeting for the first time to a national audience, did trivialise marriage and were not lawful.
"I don't even think that is legal because they haven't given the one month and one day notice so it's a big beat-up," he said.
"But I believe they (arranged marriage) can work (but) marriage has to be more than a piece of paper and people will often get married just to maintain immigration status.
"They haven't really done the right thing there. There really needs to be the real substance there."
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