In On Christian Doctrine, Augustine developed principles and rules for the interpretation of the Scriptures. In so doing, Augustine provided important and influential contributions to rhetoric, education, theology, and hermeneutics. Augustine’s hermeneutical theory should be understood in relation to his Neo-Platonic background and his attempt to come to grips with the incarnation of the divine wisdom. The Platonic chorismos schema—namely, the distinction between the changeable and unchangeable, the temporal and eternal—provides the background theory to his rules of interpretation. The changeable should be interpreted in relation to the unchangeable, the temporal to the eternal, the world to the transcendent, historical events to the divine plan of salvation, and the human Christ to the divine Word. Augustine’s hermeneutical theory bases signification on the ontological priority of the unchangeable eternal to the changeable and material.
This conviction (concerning the ontological priority of the transcendental reality over the material sign) leads Augustine to his basic principle of hermeneutics: what is of primary importance is not so much our knowledge of the material sign that enables us to interpret the eternal reality, but rather it is our knowledge of the eternal reality that enables us to interpret the material sign. This hermeneutical principle applies not only to allegorical and typological but also to literal interpretation. To understand the words of the Bible properly as signs of eternal reality, one must acknowledge that reality.