I originally read this from Wesley Hill at Writing in the Dust:
Reading the Bible out loud is a profoundly theological act. After all, it is no accident that the Christian tradition considered the Word to be first and foremost a person. In oral societies, words have so much personal power that they are treated as entities with their own agency. As Walter Ong observes, “In a society where the only known word is the pure, evanescent spoken word, it is easier to think of objects as words than it is to think of words as objects.” Reading out loud gives us a glimpse of the social conditions that made the identification of God with the Word so plausible. Reading the Bible out loud is also practically useful. It helps to answer some of the most pressing questions that arise from the written text. What did Jesus sound like when he stilled the storm, rebuked Peter, or chatted with Martha and Mary? Does it matter that the only leper who showed gratitude for being cured praised God with a loud voice (Luke 17:15)? When Pilate asked if he were the Messiah, how did Jesus say, “You say so”? How do we know, unless we try saying these words out loud ourselves? Of course, vocalizing the words of Scripture is no guarantee that they will be fully and truly understood. Such vocalization is not even a necessary condition for divine revelation, since God can work through any medium. Nevertheless, the Word of God is never more at home, so to speak, than in the sound of the human voice.
Stephen Webb, The Divine Voice: Christian Proclamation and the Theology of Sound