Assistant Speaker Trevor Mallard is objecting to the proposed new prayer for Parliament, saying while it removes religious elements from the English version, it deceptively puts them into the Maori version.
It also appeared to confer rights of Parliament's sovereignty on the local iwi, Te Atiawa.
Speaker David Carter appears to have consulted only MPs and perhaps a handful of others about changing the prayer. He won't discuss it before making the decision next week.
The prayer is said daily at the start of Parliament and has long been criticised because it is non-secular and has references to Christianity.
Mr Mallard said he was not criticising Mr Carter, but added: "The whole thing smells of consulting one or two people."
All the religion in the new prayer would be in the Maori part so the vast majority of listeners would not be aware they are listening to a prayer.
"In a way it is almost dishonest."
Mr Carter has said he won't entertain changes to the proposal. It would be the old one or the new one.
Mr Mallard: "On that basis we'll keep it as is, thank you very much."
New Zealand First opposes any change. Chief whip Barbara Stewart said it seemed they were expected to show tolerance to all faiths except Christianity, yet New Zealand remained a Christian country.