I’m always impressed with how well C. S. Lewis can articulate truths about the human condition.  It’s uncanny to me.  I think it’s one big reason why I revisit his work, some of it often.  And he does it without cluttering things up, which is a great gift for a writer to have.  Consider his thoughts on human nature from “Letter 8″ in The Screwtape Letters”:

Humans are amphibians– half spirit and half animal . . . As spirits they belong to the eternal world, but as animals they inhabit time.  This means that while their spirit  can be directed to an eternal object, their bodies, passions, and imaginations are in continual change, for to be in time means to change.

This, he asserts, ties into what he calls the “Law of Undulation,” the “repeated return to a level of from which they repeatedly fall back, a series of troughs and peaks.”  This law is at play, the master demon asserts, with “his interest in his work, his affection for his friends, his physical appetites…”  Screwtape is convinced that the secret to their infernal success would be how to make use of this reality.  It is here that he relates the key difference in the demonic view of humanity and the divine.

One must face the fact that all the talk about His love for men, and His service being perfect freedom, is not (as one would gladly believe) mere propaganda, but an appalling truth.  He really does want to fill the universe with a lot of loathsome little replicas of Himself– creatures whose life, on its miniature scale, will be qualitatively like His own not because He has absorbed them but because their wills freely conform to His.  We want cattle who can finally become food; He wants servants who can finally become sons.  We want to suck in, He wants to give out.  We are empty and would be filled; He is full and flows over.

A wonderful description of the nature of humanity (and therefore the nature of God Himself.  And near the letter’s end we get one of Lewis’s best lines.  When speaking of God, Screwtape says: “He cannot ravish, He can only woo.”