Augustine dictated a small percentage of his sermons, mostly in order to complete a running commentary, as, for example, with the sermons on the Psalms and on St. John’s Gospel. He preached most of his sermons extemporaneously, that is, without a text before him. But it’s clear that he did some research before he preached to the people, and there are many places where he runs through the opinions of others before he gives his own. Here is one place that he explains why there are obscure texts in the Scriptures.
But we mustn’t overlook another opinion. Perhaps a reason why there are obscurities in the Scriptures is so that they may give rise to many understandings, and people will go away richer when they find that what was closed could be opened in more ways than one. (EnPs 126, 11; PL 37, 1675).
He shows you what you should do when you find it hard to understand: “The Lord lifts up the gentle” (Ps 146:6). You don’t understand a text, for example; or understand only a little, you don’t follow. Well, respect God’s Scriptures; respect God’s word, even if it’s not clear to you; out of respect put off your effort to understand. Don’t be rash and attack the Scriptures for being obscure or perverse. Nothing is perverse in them; if something is unclear to you, it’s not so that it will be denied you, but so you’ll exert yourself and become capable of receiving it. When it’s unclear, the doctor did it so that you’d knock; he wanted you to work at it and knock; he wanted to open it to you when you knocked (Mt 7:7). Knocking gets you working, and when you’re at work, you broaden yourself and thus are able to grasp what is being given. Don’t be annoyed that something is closed; be meek; be gentle. Don’t be petulant and say: “If it’s going to be said that way, it’s better that it not be said at all.” ... It was said as it should have been. An ill person shouldn’t change his own medicines. The doctor knows how to modify them. Trust the doctor who’s treating you. (EnPs 146, 12; PL 37, 1907)
Still another place:
“But why do the Scriptures speak this way, in these foggy similitudes? How much better to speak openly. Why do I have to ask or wonder what these words mean? Why is it toil even to listen? Why do I sometimes go away uninstructed?” This is what I was saying a little while ago: Allow yourself to be cured; that’s how you are to be healed. A sick person is proud and hasty when he dares to instruct even his human doctor. When human beings are ill, and God cures them, it’s a great start on the way to respect and health to believe that something should have been said the way it was even without knowing why it was said. This respect makes you capable of asking what was said, and capable of finding when you ask, and of rejoicing when you’ve found it. May the affection of your prayers to the Lord our God help me, and even if not through me, may he deign for your sake to give what lies hidden here. (EnPs 147, 2; PL 37, 1914-1915)
The following excerpt perhaps indicates that Augustine as well as his hearers were aware that his interpretations were designed to amuse. The congregation must have given some indication that they liked his explanation.
Let us praise him, then: “Sing to our God.” Why to “our God?” Because “he covers the sky with clouds” (Ps 146:8) And what does that mean? He covers the Scripture with figures and mysteries. The one who lowers sinners down to the earth and lifts up the gentle, “covers the sky with clouds.” And who can see the sky when it’s covered with clouds? Don’t be afraid; listen to what follows: “”He covers the sky with clouds and prepares rain for the earth.” You became frightened at that “He covers the sky with clouds,” frightened because you don’t see the sky; but when it rains, you become fruitful and the sky clears. “He covers the sky with clouds and prepares rain for the earth”–perhaps that’s what the Lord our God has done. If we didn’t have this occasion of obscurity in the Scriptures, we wouldn’t have said the things to you that please you so much. Perhaps this is the rain that makes you glad. It wouldn’t have been possible for us to explain those things if God had not covered the sky of the Scriptures with clouds of figures. He covers the sky with clouds in order to prepare rain. This is why he wished the statements of prophets to be obscure, so that later servants of God could pour upon the ears and hearts of people who from God’s clouds receive rich spiritual joy. (EnPs 146, 15; PL 37, 1908-1909)