Science and faith were inextricably intertwined in the Latin Middle Ages. Clerics would attend to both spiritual and physical needs because the need to care for the body coincided with the need to care for the soul. Until the rise of universities in the twelfth century, monasteries were the centers of scientific knowledge. And, even after the professionalization of medicine in the thirteenth century, Christian physicians continued to look to the Bible, in addition to their license, as the source of their authority. Indeed, many Christian physicians who received medical degrees went on to pursue higher degrees in theology. It is therefore not surprising that several Christian theologians used medical theories in the service of theology.