Politicians are arriving at Rātana Pā in Whanganui for the annual celebrations commemorating the church's founder - in what is usually seen as the beginning of the political year.
It is also a rare chance for Māori to address politicians directly on the pae - and it holds extra weight this year, with the celebrations coming days after a national hui held in Waikato last weekend.
Ten-thousand people answered Kiingi Tuuheitia's call to gather for a unified response to government policies affecting Māori and Te Tiriti o Waitangi.
Key priorities identified at the hui will continue to be discussed at Rātana.
Te Pāti Māori MPs were welcomed onto the marae on Tuesday and political leaders including Prime Minister Christopher Luxon and Deputy Prime Minister Winston Peters are expected to be in attendance on Wednesday.
Labour leader Chris Hipkins is also expected to attend, along with all but three of the Green Party MPs.
RNZ's political reporter Giles Dexter said the ACT Party would not be attending which meant National leader Christopher Luxon would have to bear the brunt of criticism over the Treaty Principles bill.
Speaking at his post-cabinet press conference this week, Luxon said he was expecting to be challenged at Rātana.
"That's been my observation, that's the place where we should have challenge and provocation and stimulation and that's okay. You know, we are a country that has a diverse set of views, the day we all think exactly the same we've got a big, big problem in this country," he said.
"But it doesn't mean we can't go forward together acknowledging that we all have differences with each other as well."
Last week, a draft memo was leaked from the Ministry of Justice about the proposed bill which Te Pāti Māori co-leader Rawiri Waititi said "showed the government's intentions to erase Te Tiriti o Waitangi".
ACT has supported the bill, National has said it would support it no further than select committee.
Rātana representative Kamaka Manuel said the Rātana values of unity and peace would guide the discussion.
"The mauri of that hui will be bought down here, but our hui is always engaged with lots of spirituality and lots of wairoa, and so perhaps it's been a call this morning for us to be able to add that element to the mauri of the hui that has just finished."
The day held opportunity for politicians, Manuel said.
"The special thing about our marae is that we welcome everybody with the same essence of manaakitangi and we operate on the values and the principles and the philosophies of our founder which includes rangimarie."
He said that meant politicians would have speaking rights.
The Rātana celebration gives Māori a chance to pass on some of the kōrero from the weekend's hui at Tūrangawaewae Marae.
Speaking on the pae, Kiingitanga spokesperson Rahui Papa said he hoped the government had a plan to improve Māori outcomes - but if not, it should stay out of the way of Māori self-determination.
Māori need to be planning for how to achieve self-determination in spite of the government's plans, he said.
MP for Te Tai Hauāuru and Te Pāti Māori co-leader Debbie Ngarewa-Packer said the sentiments from the hui ā motu were being brought on to Rātana.
"That sense of solidarity I think is what's everybody's feeling great about because we know we're not alone, we know we're not wrong and we know together we're calling out a government in its anti-Māori agenda."
The theme of unity and rangatahi that emerged from the Hui ā Motu has always been a core kaupapa for the Rātana church, she said.