"Aslan is not a tame lion"

Last night we were watching the movie "Narnia" again. A line near the end of the movie jumped out at me -- it was after the battle in which the White Witch is defeated and Aslan has left. One of the children asks if they'll ever see Aslan again. The response that comes is "Aslan is not a tame lion." My interpretation? "God cannot be tamed". We can't quantify God or put Him in a box. He cannot be contained. He is that big and that powerful.