A Christian group says a bill allowing same-sex marriage does not go far enough and there needs to be a separation of the Church and State when it comes to marriage.
Labour MP Louisa Wall's Marriage (Definition of Marriage) Amendment Bill is due back in parliament on 28 February.
It aims to make it clear that marriage is a union of two people regardless of their sexual orientation or gender identity and opens the way for gay couples to adopt.
Views for and against the bill expressed at a select committee hearing in Christchurch on Monday.
Niell Ballantyne, spokesperson of the Student Christian Movement, said the Marriage Act needs a complete overhaul so that same-sex couples could get married without church ministers getting involved.
Mr Ballantyne said one way to achieve this would be to allow everyone to marry in a legal sense, and those who then wished to have another ceremony in a church could do so.
He said this would ensure that everybody was treated equally, while at the same time ensuring that church ministers were not asked to do anything that they believed would be a breach of their faith.
Mr Ballantyne said opposition to the bill is coming from a vocal minority of Christians and the majority of church-goers were not opposed to it.
But another submitter, Gavin Gilbert, rejected the suggestion by supporters of the bill that the current act does not define what marriage is.
Mr Gilbert said the institution of marriage had been established over hundreds of years and was clearly defined as between a man and a woman only.
Further submissions will be heard in Wellington on Thursday.