As Michael Hanby notes, in the Confessions, Augustine teaches that there is a “plenitude of true meanings for a single text” […] The ontological warrant that underlies this insistence throughout the Augustinian corpus derives, in part, from the very nature of truth’s oneness, which defies its circumscription or possession” (Augustine and Modernity, p. 34). For example, in Confessions XII, Augustine writes:
“Having listened to all these divergent opinions and weighed them, I do not wish to bandy words, for that serves no purpose except to ruin those who listen. The law is an excellent thing for building us up provided we use it lawfully, because its object is to promote the charity which springs from a pure heart, a good conscience and unfeigned faith, and I know what were the twin precepts on which our Master made the whole law and prophets depend. If I confess this with burning love, O my God, O secret light of my eyes, what does it matter to me that various interpretations of those words are proffered, as long as they are true? I repeat, what does it matter to me if what I think the author thought is different from what someone else thinks he thought? All of us, his readers, are doing our utmost to search out and understand the writer’s intention, and since we believe him to be truthful, we do not presume to interpret him as making any statement that we either know or suppose to be false. Provided, therefore, that each person tries to ascertain in the holy scriptures the meaning the author intended, what harm is there if a reader holds an opinion which you, the light of all truthful minds, show to be true, even though it is not what was intended by the author, who himself meant something true, but not exactly that?” (Augustine’s Confess. XII.27, pp. 327-328, M. Boulding translation).
Maria Boulding (the translator) adds the following note in regard to the passage above, “Augustine’s recognition that meanings other than those intended by the writer can legitimately be discovered in the sacred text is grounded in his conviction that the God of truth who inspired the writer and guarantees the text abides in the minds of believing readers, and that though God makes use of human words, they are never adequate to fully express his mystery; there is always a ‘plus’ of meaning” (p. 323, note 71).
We definitely have something more than gramatico-historical hermeneutics in place here. (Anachronistically speaking, our apologies to Spinoza and company).