Proposals being considered by the Anglican Church could see gay marriage services carried out in churches by gay priests.
Bishops and priests are to vote on proposals covering the blessing of same-sex civil unions, the church's response to requests to marry those couples, and ordination of gay priests.
The debate, to be heard next week at a meeting of the church's ruling body, the General Synod, has created concern it could divide parishes in New Zealand and - if adopted - cause a schism with the international faith.
The move comes against a backdrop of acknowledgement that secret blessings are being carried out contrary to church rules, and just weeks after moves to address concerns relating to lesbian, gay, bisexual and transgender members by appointing a committee to report on the issue by 2014.
The proposals could lead to a decision which would gazump the report by the committee, which includes former Governor-General Sir Anand Satyanand, High Court Justice Judith Potter and Sir Tamati Reedy.
The Anglican Church is governed from Lambeth Palace in England, which has warned the British Government it risks a split if it allows gay marriage.
Waiapu Bishop David Rice, whose diocese covers Bay of Plenty to Hawkes Bay, put forward a proposal to bless same-sex unions and ordain gay priests.
A related motion was put forward by Auckland vicar Glynn Cardy, based at St Matthew-in-the-City. He asked the synod to support parishes debating the nature of marriage and how it should be applied to same-sex relationships.
Mr Rice said part of the church might feel it better to delay a "difficult, controversial conversation", and that the current practice was for gay priests to "fly under the radar".
"I don't think there's integrity in that," he said. "How do we look upon that part of the church and that part of us? We have [lesbian, gay, bisexual and transgender] people in our church. How are we taking care of them?"
He said the issue was one of faith but also of equal rights.
The Bishop of Nelson, Richard Ellena, called the proposals a huge dilemma for the church. There would be concerns about how moves in New Zealand would affect its relationship with the international community. "I want us to remain in unity," he said.
He acknowledged his diocese was conservative. "We just don't raise it as an issue. I know it's a huge issue for many but it's not one you'll hear preached, spoken about, even debated."
Mr Ellena said he had heard of rogue blessings of gay couples being conducted in Anglican churches.
Massey University associate professor Peter Lineham, an expert on English and New Zealand religious history, said he believed the proposals were likely to lead to gay priests and gay marriage. Preliminary votes among the seven dioceses in New Zealand had led to support from four.
"The bishops have been walking very carefully because they are nervous they'll be held responsible for the Anglican Church falling apart."
Mr Lineham, who is gay and Christian, said the "liberal phase" of the church internationally was in decline. The greatest church base was in Africa where conservative attitudes were dictating its approach.