Jonathan Benjamin is facing 20 charges, including four of rape, during his time at the Gloriavale Christian Community between 1986 and 2017.
Crown lawyer, Kerry White, says some of the complainants were aged between six and 14 when they say they were attacked.
The five complainants, police and other witnesses will give evidence over the next three weeks.
Nive Chittock reports from the Greymouth District Court.