Former Governor-General Sir Paul Reeves has been diagnosed with cancer.
Sir Paul was the first head of state to be of Maori descent and also the first clergyman to be appointed to the role.
He will withdraw from all public roles to spend more time with his family and has asked for privacy.
Sir Paul started his career as a deacon in the Anglican Church of New Zealand in 1958 and over the following twenty years moved up to become the Bishop of Auckland in 1979 and Primate and Archbishop of New Zealand in 1980.
He took the role as Governor-General in 1985 and served for five years.
In more recent times he has been the Anglican Observer at the United Nations in New York and represented the commonwealth in talks with Fijian leader Frank Bainimarama.
Last year he led a group of eminent people who called on the Government to take firm measures to address the country's "alcohol crisis".
In 2007 he was admitted to the Order of New Zealand, the country's highest honour.
He was also the first and current Chancellor of Auckland University of Technology.
A colleague of Sir Reeves is describing him as a man who is never afraid of speaking out on issues.
Bishop of Taranaki Philip Richardson has known Sir Paul for over 30 years.
He says Sir Paul has definite views and expresses them clearly.
Richardson says he's spoken out on many issues from a nuclear-free New Zealand to land and Treaty-based issues.
He says he has given his views on a whole raft of concerns including poverty.
- with Newstalk ZB