I did appreciate Keller working through at length how doctrine and experience go together. Christian mediatation needs to be deeply rooted in the Word. If we have alone time where we just sit and contemplate the things of God we need to understand what he's already told us about himself if we're to think correctly about him.
Keller wraps up the chapter with a quote from Augustine explaining where proper meditation of the Word can lead us.
"But what do I love when I love you? Not the beauty of any body or rhythm of time in its movement; not the radiance of light, so dear to our eyes; not the sweet melodies in the world of manifold sounds; not the perfume of flowers, ointments and spices; not manna and not honey; not the limbs so delightful to the body's embrace: it isnone of these things that I love when I love my God.
And yet when I love my God I do indeed love a light and a sound and a perfume and a food and an embrace - a light and sound and perfume and food and embrace in my inward self. There my soul is flooded with a radiance which no space can contain; there a music sounds which time never bears away; there I smell a perfume which no wind disperses; there I taste a food that no surfeit embitters; there is an embrace which no satiety severs. It is this that I love when I love my God"