Parts of the education sector may again seek greater clarity around the use of karakia in schools when a parliamentary select committee considers a law change to religious instruction in schools.
But National's Nikki Kaye says the committee would require special cultural advisers.
Karakia are delivered in Maori at the beginning of meetings, or sometimes classes, or before a meal as a form of prayer or blessing.
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They are a basic part of Maori tikanga, or custom, and can be full of religious references to Jesus Christ and God, or more traditional with references to Maori Gods and creation characters such as Papatuanuku, or without reference to either.
The School Trustees Association, representing about 2250 school boards, last year sought urgent clarification about the relationship between Maori tikanga and religious observance.
It sought advice when making a submission on the Ministry of Education's Guidelines for Religious Instruction but when the guidelines were issued, they were silent on karakia.
"One issue that requires urgent clarification is how religious observance and tikanga Maori relate to each other," the submission said.
"Spirituality is an important aspect of te Ao Maori and since the advent of Christian missionaries, Christian forms and beliefs have become an integral part of that spirituality."
That created mixed messages in the ministry's attitudes to biculturalism and to secular state education, the submission said.
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"The difference between prayers and karakia is a current example of a question that has underpinned tensions between school communities, boards and staff for many years.
"What constitutes substantive religious practice? Where is the boundary between religious practice and social or cultural custom?"
The submission said that when there were mixed messages, obligations under the Treaty of Waitangi should be given precedence.
Parliament's education and workforce select committee will be hearing public submissions on the Education and Training Bill which, among many other measures, will require parents to give written consent for their children to take part in religious instruction in any state school.
Under the present law, the onus is on parents to opt out of any religious instruction which may be offered when the school is closed for up to an hour a week. The bill does not cover karakia but it is likely to be raised in wider submissions on religion in schools.
Nikki Kaye said the committee would require special cultural advisers if the religious instruction measures opened up broader submissions.
"National is supportive of schools being able to have religious instruction whereby parents are brought into that process," she said.
"We think it makes sense to have a pretty health debate about these issues and an opt-in process maybe clearer for everyone.
"But I think the complexity of issues like the karakia and potentially other cultural practices…possibly across a range of cultures, not just Maori, are issues that we are going to need to work through and we are going to need to have pretty special advice via the select committee process."
A spokeswoman for the Secular Education Network, Sonja Farmer, thought it would be good to have greater clarity around karakia.
"We certainly need more clarity around it," she said. " The Treaty of Waitangi gives tangata whenua right to religious expression but with schools being secular in nature, that is where that clarity needs to be.
"It would be lovely if karakia could perhaps take a more traditional route because there are some lovely karakia that are not Christian-based and would be a lot more appropriate for primary schools to be involved in."
Labour list MP Willie Jackson said there were legitimate questions to be asked religion and karakia and their ramifications "because our society is changing."
In his own home before a meal, the karakia might be religious or traditional depending on who was saying it.
In state schools? "Maybe they can opt in and the schools can make a choice but I think any type or karakia is good for schools," he said, stressing it was a personal view.
"I've seen it enrich people's lives."
He had worked with people who did not have any sense of spirituality or Maori worldview in their lives.
"Any slice of that in my view would have helped in turning their lives around. I don't care what karakia they use, personally. I don't care what church they are with personally," Jackson said.
"I've seen no evidence that spirituality has hindered or stuffed up people's lives. It will always get my support. I'm not rabid about which karakia or which church people follow."