The Screwtape Letters, Session 3: The Trough Is Where the Work Begins

Wormwood has written to report what he thinks is good news. His patient’s religious phase, he says, is “dying away.” The early warmth has gone out of it. The man still goes through the motions, but in a low mood. Wormwood, being young, thinks the patient has accepted defeat.

Screwtape’s reply in Letter 8 is withering. He begins by insulting his nephew’s education and then asks a question that stops us in our tracks: “Has no one ever told you about the law of Undulation?”

In explaining the law to Wormwood, Screwtape reveals why dying-away periods are not evidence that the spiritual life has failed. They are the conditions under which a person begins to choose apart from mood.