Laid up in the heart

From the additional notes to Charles Spurgeon's The Treasury of David, Psalm 119 verse 11. 

Thy word have I hid in mine heart, that I might not sin against thee. There laid up in the heart the word has effect. When young men only read the letter of the Book, the word of promise and instruction is deprived of much of its power. Neither will the laying of it up in the mere memory avail. The word must be known and prized, and laid up in the heart; it must occupy the affection as well as the understanding; the whole mind requires to be impregnated with the word of God. Revealed things require to be seen. Then the word of God in the heart— the threatenings, the promises, the excellencies of God's word— and God himself realized, the young man would be inwardly fortified; the understanding enlightened, conscience quickened— he would not sin against his God. John Stephen.