Bruce McNab earned a doctorate in medieval history from Princeton.

His first publication was Military Arrays of the Clergy in England, 1369-1418, an essay in a volume published in honor of the late Joseph R. Strayer, entitled Order and Innovation in the Middle Ages (Princeton U.P., 1976).

He was ordained as an Episcopal priest and became a parish priest and pastor, serving six parishes between 1974 and 2011. He was active as a teacher, guest speaker, workshop leader and consultant.
Retired from full-time parish work in 2011 he moved to Bozeman, Montana and became the permanent part-time priest at Christ Church in the small town of Sheridan, Montana.