He worked for two years with the Student Christian Movement as secretary to theological colleges (1951–1953), studied briefly in Basel with Karl Barth and Oscar Cullmann, before marrying his first wife and SCM colleague Frances Paton (granddaughter of John Gibson Paton) and moving to India as Christian missionaries in 1954.

In 1959, Boyd returned to Edinburgh to begin his PhD on the subject "The Place of Dogmatic Theology in the Indian Church.

"[1] He was appointed to the Gujarat United School of Theology in Ahmedabad in 1961 and witnessed the formation of the Church of North India in 1970.

He later served as director of the Irish School of Ecumenics (1980–1987) before returning to Melbourne for parish ministry and retiring in 1994.

His PhD thesis was published in 1969 as An Introduction to Indian Christian Theology, and revised and expanded in 1975.