"And I think that as a society we have to re-engage in a dialogue with faith, and to recognise that faith, hope and love are values that society depends upon," he said.
Bishop Duckworth began his Christian work after leaving school.
In his early 20s, he and his wife, Jenny, began running a home for teenage women in the Wellington suburb of Berhampore.
With other Christian activists, the couple later formed Urban Vision to help those who were struggling.
They also started Ngatiawa, a contemporary monastery in the Reikorangi Valley on the Kapiti Coast, which last year provided accommodation to 1100 visitors.
Bishop Duckworth's election was welcomed by Archbishop David Moxon.
"The Electoral College clearly identified Justin's Christian lifestyle, Christian discipleship and Christian mission as key - and I am confident that his election will challenge, invigorate and grace the church with a deep sense of the breadth and height and depth of the love of God."
Bishop Duckworth replaces Bishop Tom Brown, who has retired.