Dallas Willard's words

"Bible memorization is absolutely fundamental to spiritual formation. If I had to choose between all the disciplines of the spiritual life, I would choose Bible memorization, because it is a fundamental way of filling our minds with what it needs. This book of the law shall not depart out of your mouth. That’s where you need it! How does it get in your mouth? Memorization." ("Spiritual Formation in Christ for the Whole Life and Whole Person" in Vocatio, Vol. 12, no. 2, Spring, 2001, p. 7, as quoted by John Piper here, bold added)