Satan's actions - Screwtape

Lines around 210 through 220 describe Satan's actions meant to hurt people ending up good, light, or in order instead of towards disorder. Milton says "while he sought Evil to others, and enrag'd might see How all his malice serv'd but to bring forth Infinite goodness, grace and mercy shewn On Man by him seduc't, but on himself Treble confusion, wrath and vengeance pour'd." This reminds me of Screwtape Letters because wormwood's "patient" goes to church, becomes friends with religious people, prays, or does something for God after wormwood tried to negatively influence him. Screwtape advises wormwood several times and later finds out that the patient reacted by praising God in someway. The slight difference between praying towards god versus an idol constantly gets wormwood into trouble or danger of losing his patient. I guess I'm trying to say that evil is defeated often and enraged as a result. Also, the margin by which evil loses is very small from slightly changing an action or thought. Satan tries to negatively influence humans, but often finds that he does good. This must be frustrating if you want to do everything that is not good. God seems to clearly by the ultimate god and creator. Does this make sense?