Not desiring, but still intending

Regarding Mother Teresa's dark night half-century of the soul, a reader kindly reminded me of this great quote from C.S. Lewis's The Screwtape Letters.  As Screwtape wrote to Wormwood,

"Our cause is never more in danger than when a human, no longer desiring, but still intending, to do our Enemy's will, looks round upon a universe from which every trace of him seems to have vanished, and asks why he has been forsaken, and still obeys."