Chapter 23

Wormwood's patient has died, and, much to Screwtape's dismay (at losing a soul) and delight (at the pleasure of Wormwood's punishment), the patient is with the Enemy.

Confronted with the reality that Wormwood has not made effective use of cowardice in subverting the Enemy's hold on Wormwood's patient, Screwtape encourages Wormwood to take advantage of fatigue as an assault on the patient's perception of what is "real."

Screwtape confirms that the Germans are going to bomb the area where Wormwood's patient lives and discusses the ramifications of encouraging the patient's cowardice.

Screwtape explains to Wormwood the importance of time in corrupting souls against the Enemy and impresses on Wormwood the counterintuitive need to keep his patient alive through the war.

Finding that Wormwood has allowed his patient to be aware that he is distracted during his prayers, Screwtape instructs Wormwood on how to undermine the patient's belief in answered prayers.

Screwtape advises Wormwood on all the ways that Unselfishness can be used to create bitterness and resentment between Wormwood's patient and the patient's girlfriend.

Screwtape notes that Wormwood's patient's religious experience is "mere" Christianity, and he coaches Wormwood to focus his efforts on subverting the patient's fundamental beliefs by encouraging "Christianity And..." as well as interrupting the patient's balance between change and permanence.

Screwtape sees that Wormwood's patient is vulnerable to developing Spiritual Pride at being accepted into a Christian circle of friends. Screwtape advises Wormwood on how to take advantage of this.

Finding that Wormwood's patient, through the girl he has fallen in love with, is meeting new Christians, Screwtape instructs Wormwood on how to corrupt the patient's spirituality by focusing the patient's interests on the social implications of his religion, especially on the idea of an historical Jesus.

Screwtape castigates Wormwood for letting Wormwood's patient fall in love with a Christian woman. The end of the letter is transcribed by Screwtape's secretary, Toadpipe due to the unfortunate mid-rant transformation of Screwtape into a large centipede.