Cordially Yours, Brother Cadfael

Detective, monk, father, herbalist, Crusader, sailor, Celt, friend-author Ellis Peters bestows all these attributes on her twelfth-century Benedictine monk-detective Brother Cadfael. As a detective, Cadfael uses his analytic mind to solve crimes and administer justice. As a man of God, he also dispenses mercy along with his famous cordials.
Why, essays ask, is a cloistered monk solving murders? How can an author combine a valid detective and an effective healer?