I have stored up your word in my heart, that I might not sin against you. Psalm 119:11
The entirety of Psalm 119 is written as an acrostic in Hebrew. There are twenty-two stanzas in the huge poem. Each stanza is eight lines. Each line starts with the same letter of the Hebrew alphabet. It was written, in other words, to be memorized.
The purpose of the memorizing is written in this verse – that I might not sin against you. First, he realizes his potential for sin. He knows that without some external force or influence in his heart, he would sin. He knows that his heart is fallen. Do we know this about ourselves?
The action he takes in response to this self-knowledge is to store the words of God within him. His sick heart needs a medication. And the medication is God’s word. When he reads it, he doesn’t allow it to pass through his brain. He latches onto it. He thinks hard about it. He remembers the actual words.
And look at where he is storing them up – his heart. This word means the mind, the will, the inner-man. It means the real you on the inside. He isn’t trying to impress anyone with how much Bible he knows. He isn’t aiming at mere recitation knowledge. If you have tried memorizing before, you know it is entirely possible to recite perfectly thirty verses of the Bible, without one of them actually registering anything meaningful in your heart.
What hope this offers to sinners like us. There is a medication for our sick hearts. The Word of God stored up, loved, treasured, hidden away inside of us, does not change us the way a witch turns someone into a toad. Instead it is like Vaseline applied to dry skin. It changes us, because it heals us. It changes us, because it binds up the festering wounds caused by our sin. It allows us to transform into who God made us to be. This transformation, is what keeps us from future sin.