Symbolism, Imagery, Allegory
Clever, clever, Augustine. By using the soul as a metaphor for the body, Augustine is actually being really clever. It may seem like old hat now to say that your soul is sick. But you know how Augustine has a hard time imagining God because God is immaterial? And you know how the Manichees see all things as made up of good and evil particles? Even though people believed they had souls way before Christianity came along, there were a lot of different ways of imagining the soul. Augustine has trouble defining the soul at times, and he thinks for a living, for goodness sake.
But the body is pretty self-explanatory. It indisputably exists. You can picture it, you can even feel it. And when something is wrong with it, you need to take care of it or you might die. By treating the soul as though it were something like the body, which needs to be nourished and cared for in order to thrive, Augustine is getting us to think of the soul with the same sense of urgency.
Egads, Your Soul Is Sick
Thinking of the soul as a body type thing allows Augustine to talk about his godlessness as if it were an affliction. In fact, sometimes he even makes it sound like his spiritual disease is a physical disease, only without the huge medical bills. Hey, what better way to illustrate a condition than to compare it to something that everyone can relate to?
Let's look at some of the ways Augustine talks about the sick soul-as-body:
I felt no need for the food that does not perish, not because I had had my fill of it, but because the more I was starved of it the less palatable it seemed. Because of this my soul fell sick. (III.1.1)
But where the fingers scratch, the skin becomes inflamed. It swells and festers with hideous pus. And the same happened to me. (III.2.5)
Augustine will occasionally talk about the soul being nourished and healthy, but for the most part, he discusses how the soul is decrepit and dying.
Calling Dr. Love—Er, We Mean God
So, if the soul is like the body, and it can get sick sometimes, then God can act like a doctor and help cure what ails ya. (We like to imagine Dr. God to be someone like Dr. Cox.) The interesting part is that God will give you the things you need to be cured, but He will not smite your wickedness for you. Only you can do that.
Augustine refers to Dr. God all the time in the Confessions. For example, he says:
Let them not deride me for having been cured by the same Doctor who preserved them from sickness. (II.7.2)
See, God is even a capital-D Doctor. You know, like, The Doctor. (No, not that doctor.) Augustine also likes to call God the "Physician of my soul" (X.3.2). Fancy.