The question of whether silent reading was unusual during Augustine's time is explored through a passage from Augustine's Confessions (6.3.3.). In this passage, Augustine reflects on the reading habits of his mentor, Aurelius Ambrosius, the archbishop of Milan, who read silently. This observation suggests that silent reading may have been uncommon in that era. Augustine notes, "When Ambrose read, his eyes ran over the columns of writing and his heart searched out the meaning, but his voice and his tongue were at rest. Often when I was present—for he did not close his door to anyone and it was customary to come in unannounced—I have seen him reading silently, never in fact otherwise. I would sit for a long time in silence, not daring to disturb someone so deep in thought, and then go on my way. I asked myself why he read in this way. Was it that he did not wish to be interrupted in those rare moments he found to refresh his mind and rest from the tumult of others' affairs? Or perhaps he was worried that he would have to explain obscurities in the text to some eager listener, or discuss other difficult problems? For he would thereby lose time and be prevented from reading as much as he had planned. But the preservation of his voice, which easily became hoarse, may well have been the true cause of his silent reading."
Alberto Manguel's book, A History of Reading (1996), dedicates Chapter Two to "The Silent Readers," discussing the prevalence of reading aloud since the inception of written language. The first printing of St. Augustine's Confessions was issued by printer Johann Mentelin of Strasbourg no later than 1470. A digital facsimile of this edition was made available by the Bayerische Staatsbibliothek in November 2013. Additionally, a German biographical film titled Des Leben des heiligen Augustinus (2010), featuring Franco Nero, provides an authentic depiction of book rolls and early codices during the transition from the roll to the codex.