In Confessions 4.5.10, Augustine takes up the difficult question of why we often find grief and sadness to be, in a sense, pleasurable, without coming to a definite conclusion. The question is closely related to the theory of tragedy as a literary and dramatic genre (perhaps glanced at with the mention of Orestes and Pylades in 4.6.11), but that is not my purpose here, which is:

In describing his state after the death of his unnamed friend, Augustine says: miser enim eram et amiseram gaudium meum (“For I was wretched and I had lost my joy”). There is a great bit of wordplay here: miser enim eram et amiseram gaudium meum. Though the words for “I was wretched” (miser…eram) and “I had lost” (amiseram) are etymologically unrelated, Augustine connects them through their similarity in sound as a way of linking effect and cause, as if to say: “I was wretched, and the reason was that I had lost my joy.”

In this way, Augustine can introduce the idea of cause into the sentence through the back door, as it were, even though he uses the conjunction “and” (et) rather than a causal conjunction to join the two clauses.