Though scriptural memorization ultimately serves a number of sanctifying ends (cf. Ps 119:11), it also serves the process of reading. Scripture is characterized by a rich intertextuality. On almost every page, the Bible either quotes or alludes to other biblical passages. Closely related to this phenomenon, the Bible projects an internally coherent symbolic world. Accordingly, symbols in one text shape the way we interpret symbols in another text.–Scott R. Swain, Trinity, Revelation, And Reading: A Theological Introduction to the Bible and its Interpretation, 123-24.
Given this fact, much of the biblical message will be lost on us if we are not intimately familiar with the symbolic and allusive features of its textual reality. Memorization is one of the best ways of establishing such intimate knowledge.