Screwtape strategizes with Wormwood, using Time as a weapon:
I had noticed, of course, that the humans were having a lull in their European war—what they naïvely call ‘The War’!—and am not surprised that there is a corresponding lull in the patient’s anxieties. Do we want to encourage this, or to keep him worried? Tortured fear and stupid confidence are both desirable states of mind. Our choice between them raises important questions.
The humans live in time but our Enemy destines them to eternity. He therefore, I believe, wants them to attend chiefly to two things, to eternity itself, and to that point of time which they call the Present. For the Present is the point at which time touches eternity. Of the present moment, and of it only, humans have an experience analogous to the experience which our Enemy has of reality as a whole; in it alone freedom and actuality are offered them. He would therefore have them continually concerned either with eternity (which means being concerned with Him) or with the Present—either meditating on their eternal union with, or separation from, Himself, or else obeying the present voice of conscience, bearing the present cross, receiving the present grace, giving thanks for the present pleasure.
From The Screwtape Letters
Compiled in A Year with C.S. Lewis