Macquarrie was educated at Paisley Grammar School before studying philosophy at the University of Glasgow under the distinguished scholar Charles Arthur Campbell (MA 1940) and obtained a degree in theology (BD 1943).

He was ordained as a Presbyterian minister in the Church of Scotland in 1945 and then served in the Royal Army Chaplains Department (1945–1948).

His supervisor was Ian Henderson who, despite having been a pupil of Karl Barth at Basle, was theologically more closely aligned with his disputant, Rudolf Bultmann.

During his time in the United States Macquarrie became a member of the Episcopal Church, part of the Anglican Communion.

His involvement in the Episcopal Church in the United States eventually led him to be ordained priest by the Bishop of New York on 16 June 1965.

On the next day (the Feast of Corpus Christi) he celebrated his first Eucharist at the Church of St Mary the Virgin in New York City.

His work is characterised by even-handedness to all sides and viewpoints and, although not always readily accessible to those without a good background in philosophy, his writing is considered[who?]

In his book Mediators Between Human and Divine (1996),[5] he wrote: In 1964 I published an article entitled 'Christianity and Other Faiths'... [and] I continue to hold the views I expressed then...

I drew the conclusion that there should be an end to proselytizing but that equally there should be no syncretism of the kind typified by the Baháʼí movement.

(p. 2)[5] In that book, Macquarrie commented on what he called nine historical figures who were viewed by their followers as mediators between the human and the divine.