An overwhelming majority of churches would not host a same-sex wedding, even if the law is changed to allow it.
Almost all the major Christian denominations have vowed not to officiate for gay marriage, as have most other religious groups.
The same-sex marriage bill passed its first reading in Parliament this week and must now pass two more readings before it can become law.
But Catholics, Anglicans, Baptists and many other smaller denominations have already joined Muslims, Hindus, Sikhs and Orthodox Jews in prohibiting gay marriages on their turf.
Only a handful of churches are standing behind the bill.
Labour MP Louisa Wall, champion of the gay marriage bill, said the tepid religious support for the bill was no surprise.
"I anticipated that . . . but that's their choice. I believe every New Zealander should be free from discrimination but we [also] uphold the right for freedom of religion.
"Over time we may find ministers say, ‘Yes, we will marry.' One of my ministers [in my constituency] said that for him the Bible is a living document.
"For him it's about the community that's in front of him now. If you view it in that context, it [the situation] will change over time."
Presbyterian minister Margaret Mayman, of St Andrew's on the Terrace in Wellington - one of the few Christian ministers to support the bill - believed a law change would gradually become accepted.
"There's a fairly familiar pattern," she said. "First of all people are in denial . . . then gradually admit some exceptions, and then suddenly it's fine."
But many religious leaders' views appear set in stone.
Anwar Ghani, president of the Federation of Islamic Associations of New Zealand, said Muslim law made it clear gay marriages could not be accepted.
"Our position is very clear: Islam does not allow marriages of same sex. Islam views marriage not just for recreation, but for procreation," he said.
Lali Singh, general secretary of the New Zealand Sikh Society, said: "We will not allow any gay marriages in the temples. It's against religious rules - it should be just between a man and a woman." And the Catholic Church has spoken out repeatedly against Ms Wall's bill.
Associate professor in religious studies at Victoria University, Chris Marshall, said he could understand the churches' reluctance.
"In many cases what you will probably find is there's a very long and rich theological reflection on the meaning of marriage and the family that simply can't be changed overnight.
"It takes time.
"I can see why religious groups have been put on the back foot."
- © Fairfax NZ News
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