Confession: I sometimes skip to the back of the book. This is a sacred taboo for an author, I know, but what can I say? I don’t read the entire back of the book, mind you, just a small spoiler. In fact, the better the book, the more likely I am to skip ahead and make sure the characters don’t die before the end of it. I figure if they’re still alive on page 217, I can relax and listen to their emotional drama in Chapter Four.

It is a habit that drives my family nuts.

One of my favorite books is The Screwtape Letters, by C.S. Lewis. As C.S. Lewis fans know, the book is a collection of letters written from the perspective of a senior demon to his trainee, a junior demon. Lewis’ complex wit and profound simplicity are never displayed better than in this compilation of advice on how to derail Christians, all told from the perspective of the enemy.

As many times as I’ve read it, I never understood one of the main lessons of the book until just recently. There are a great many principles, but the one that stands out the most is how the enemy often uses the subtle corrosion of good things to trip up even the most devout.

It’s not a direct attack or even a blindside, but a slow poison. It’s not the invention of new evil, but a tarnishing of the good. The enemy doesn’t have to create a Temptation Island of wickedness to suck you into a den of evil if he can distance you from God using a combination of DVRs, video games, Facebook, Twitter or even your kids. He doesn’t have to use a temptress to destroy your marriage if he can wreck it over finances, emotional baggage lack of communication, bitterness or too much time on the Internet. He doesn’t have to make you hate your neighbor if he can convince to you simply ignore them. He doesn’t have to create bad things to wreak havoc in our lives – all he has to do is spoil the good things. The rest will generally take care of itself.

Why does he use this technique? Because we’re usually on the lookout for sheer wickedness – the “bad things.” We have our highest defenses up against those. What we aren’t necessarily expecting are small, seeds of pollution – indiscernible at first – which get you used to their presence and then blossom into a tangled vine of bitter weeds.

In other words, the enemy can be subtle. Where an outright assault on principles of our virtue might fail (or at least send up a warning), the gradual, chipping away or tarnishing of a blessing can have the same end result. He doesn’t have to take a good thing away from you – a spouse, a relationship, a job, your walk with God, even the church – if he can spoil it.

To put it in the words of Screwtape:

You will say that these are very small sins; and doubtless, like all young tempters, you are anxious to be able to report spectacular wickedness. But do remember, the only thing that matters is the extent to which you separate the man from the Enemy. It does not matter how small the sins are provided that their cumulative effect is to edge the man away from the Light and out into the Nothing. Murder is no better than cards if cards can do the trick. Indeed the safest road to Hell is the gradual one – the gentle slope, soft underfoot, without sudden turnings, without milestones, without signposts.”

Spoiler alert.