I've been thinking lately about how we as human beings just don't have the ability to wrap our 3 lb. brains around God, much less explain him fully to others. It seems to me that the only ways we can even talk about God are anthropomorphically (giving human traits and characteristics to something that is not human, i.e. "the flower turned its face toward the sun" or "the skies wept"), analogically (through the use of analogy), or metaphorically. I guess that's why it bugs me when I hear people describe God with such certainty. ("God IS like this." "God couldn't possibly be/do/feel that") As Brian McLaren says, most people actually just think of God as a bigger, better version of themselves. The use of the three language devices I have listed (anthropomorphism, analogy, or metaphor) in relation to God necessarily implies that we don't or can't exactly know. When we use these devices we are, by necessity saying "it's kind of like this, but not exactly". It's a stance of humility (and one that scripture actually takes in describing God as well). It's saying "I only know what He has chosen to reveal to me, and I have to relate it to my experience in order to even begin to grasp it."
Even when Jesus explains the Kingdom of God, He speaks parabolically. We want Him to do a detailed, logical exposition. Instead, He always says "The Kingdom of God is like this: Once upon a time, there was a..." On top of that, these parables aren't even allegorical, where you can just figure out the symbolism and fill in the blanks, and it's a rare exeption when He gives any kind of explanation whatsoever. Instead, what Jesus does with parables is create worlds full of things from the experience of his listeners, only the worlds created by His stories don't quite operate the way ours does. Tom Wright says that parables are like plays looking for actors, and our job is to figure out where we fit in them. Jesus, instead of giving us steps, rules, and models for the Kingdom of God creates new ideological worlds with his stories and invites us to join the cast.