Early life and pastoral career
Chamberlain was born in
Christchurch, New Zealand, the eldest son of Ivan and Greta Chamberlain.
 His father served as a
warrant officer in the
Royal New Zealand Air Force during
World War II, while his mother was involved with the administration of the
Seventh-day Adventist Church in southern New Zealand.
Lincoln High School and
Christchurch Boys' High School, Chamberlain commenced studies at the
University of Canterbury but after converting to the
Seventh-day Adventist Church in 1965, he left and migrated to Australia.
 He subsequently studied at
Avondale College in
Cooranbong and graduated with a
Bachelor of Arts (Theology) degree in 1969.
 He married
Lindy Murchison the same year, after meeting her in 1968.
After graduating, Chamberlain worked as a Seventh-day Adventist minister in
Tasmania, where Lindy Chamberlain gave birth to two children—Aidan (born 1973) and Regan (born 1976).
 In 1977 the family moved to
Queensland, where Chamberlain produced and presented a radio program called The Good Life, a commentary on lifestyle and culture throughout the northern parts of the state.
 The Chamberlains' third child, daughter Azaria, was born in
Mount Isa on 11 June 1980.