Augustine's use of medical imagery in his polemical theology

In his three major polemical campaigns, that is, against the Manichees, Donatists and Pelagians, Augustine used imagery derived from medicine and was, in tum influenced by the language he used. While much of the language of sickness and disease remained conventional, some usages came to bear significant theological weight, notably infirmitas and contagio. The former became a designation for the culpable weakness affecting each member of the human race since the Fall. The latter became a technical term for the transmission of original sin associated with concupiscentia. Sickness imagery assumes the analogy of the soul and body, advancing his project to integrate the two parts of the human person. It also enabled him to discuss humanity's fallen nature without slipping into Manichaean determinism or Pelagian autonomy. Finally, sickness imagery enabled Augustine to suspend the tension between the inherited guilt and free-will in readily accessible metaphor. Images of health and healing also helped Augustine sustain tensions in his thought. But even more significantly, the image of Christ the Physician proved critical throughout his polemical career. Against the Manichees it is the Divine Physician who lays out the stages of sacred history according to a great therapeutic strategy for the human race. Against the Donatists it is the wisdom of the Physician who prescribes painful means of cure which is urged against Donatist complaints of persecution. Finally, against the Pelagians, Christus Medicus becomes a technical soteriological term. This family of metaphors, drawn from the Scriptures, classical literature, pagan religion and common experience appear time and time again. While they may have become commonplace in the writings of other Christian authors, in Augustine's polemical theology they came to shape and inform key aspects of his thought