December 2023
What If Thoughts Can Be Evil?

We don't often view thoughts as "evil" things. But they certainly can be. Thoughts can be powerful in drawing us either towards God or away from him. We'd like to believe that thoughts are neutral. But that's exactly what Satan wishes for.

One of the many telling lines in C. S. Lewis's The Screwtape Letters is this one, from one devil to another, "It is funny how mortals always picture us as putting things into their minds: in reality our best work is done by keeping them out" (Letter 4). Keeping what out of our minds, exactly? Here's one example: the idea that thoughts can be evil or demonic.

I realize in our contemporary secularized culture, where everything has been de-supernaturalized, that's a lot to take in. "Aren't thoughts just . . . thoughts? Synapses firing in the brain? You don't have to go all medieval on something that has a perfectly grounded medical and scientific explanation." I hear you. Really, I do.

What If

But what if that is exactly what demons want? Screwtape told his nephew that they do their "best work" by keeping things out of our heads, not putting things into them. What if they've been celebrating since the Enlightenment because people mostly assume that thought is a neutral, physiological phenomenon? What if Satan celebrates the fact that many Christians view their thought lives as neutral?

What if Satan celebrates the fact that many Christians view their thought lives as neutral?

I'm reminded of a similar what-if that John Mark Comer draws out, as he builds on the work of Evagrius (a monk of the early church) in Live No Lies:


For Evagrius, logosmoi, or our thought patterns, are the primary vehicle of demonic attack upon our souls. That might sound far-fetched to our skeptical Western ears, but think about it: Have you ever had a thought (or feeling or desire) that seemed to have a will to it? An agenda that was hard to resist? And not thinking it felt like fighting gravity? It seemed to have a weight or power over you that was beyond your ability to resist? Could it be that the thoughts that assault your mind's peace aren't just thoughts? Could it be that a dark, animating energy is behind them? A spiritual force? Could it be that this is about more than mental hygiene or positive thinking; it's about resistance? (John Mark Comer, Live No Lies, p. 86)

"A dark, animating energy". . . Yea. What if thoughts aren't just synapses firing within the soft walls of our brain tissue? What if a thought could be a weaponized? Would that change the way we walk through life each day?

I think it would. And doesn't this make a bit more sense out of Paul's call to spiritual warfare in Ephesians 6:12? We're fighting against things that sound pretty abstract to 21st century Western ears: cosmic powers and spiritual forces of evil. And that's not just a fraction of the enemy; that's the enemy. Our war isn't against "flesh and blood"; it's against this.

What Makes a Thought Evil?

"Hold up," says the well-rounded Christian skeptic (is that an oxymoron?). "How can you possibly link thoughts with these things?" Well, think about what our spiritual enemies do. Then think about what a thought can do. Satan and his servants want to do essentially three things. They want to take us . . .

  1. Further from God. We only move in two different directions: either towards God or towards Satan. That's it. There's no neutral zone. Moving in God's direction means moving deeper into relationship with him so that we start to resemble our creative, loving, generous, patient, self-giving Lord. Moving in Satan's direction means becoming a black hole for all goodness. We become destructive, malevolent, hoarding, quick-tempered, self-seeking centers of chaos.
  2. Deeper into doubt. If Satan can get you to doubt God and his promises, he's already won the hardest part of the battle. Genesis 3 is a case in point. Doubting God's goodness led immediately to breaking his law, which led to death and a kingdom of curses.
  3. Lower into self-absorption. The devil's aim is to bend our backs so much that we stare at ourselves for eternity. He wants each one of us to be as self-absorbed as possible, the practical center of our fantasy universe.
The devil's aim is to bend our backs so much that we stare at ourselves for eternity.

Now, if a thought does one of these things—if it takes us further from God, deeper into doubt, or lower in self-absorption—wouldn't you feel comfortable classifying it as a weapon of the enemy, an agent of evil?

Identifying a Thought as Evil

"But how do you know the difference between an evil thought and a sinful thought or a plain old synapse firing?" That's an important question. There are plenty of passages in the Old and New Testaments to help us identify evil as such. One of the most helpful to me recently has been Romans 14:23. "Whatever does not proceed from faith is sin." A lustful thought, for instance, even for your spouse, does not proceed from faith. So, you can identify that thought as sin. But what about identifying it as evil?

Though it's not a fail-proof method, in addition to paying attention to the criteria above, we would do well to note the persistence of the thought. Does the thought keep coming back, over and over again? Does it seem to bind you with invisible chains, drawing you away constantly from God, pushing you to doubt, encouraging self-focus? Chances are, that's evil.

Consider the man Jesus encountered in the country of the Gerasenes in Mark 5 (also in Matt. 8 and Luke 8). This was a man bound persistently by evil, so much so that no one could even cross his path. He spent his days bursting through chains, crying out to the landscape, and cutting himself with stones. He was a man of curses, chaos, and blood. Surely, this was drawing him always further from God, deeper into doubt and despair, and lower into self-absorption. And this became not just a frequent occurrence, but his life. It consumed him.

And look at what it says after Jesus cast out the demons from him and sent them into a herd of pigs. He was sitting with Jesus (closer to God), clothed (trusting in God's provision), and "in his right mind," able to recognize and acknowledge others (5:15). If he was in his "right mind" after Jesus healed him, then he was in his "wrong mind" before that. His thought life was evil.

So, can a thought be evil? It sure can be. That's a truth Screwtape would rather keep out of your head.


Now, this doesn't mean that if you have a negative thought following you around for a few days, then a demon is working to control you. We're limited in what we can know about spiritual things. And when we're quick to draw conclusions, we're often leaving out complexities and being reductionistic.

But what makes me nervous, what would have Screwtape and his nephew smiling, is the fact that we assume thoughts are neutral, that there's no way they could be evil, that demons and the forces of Satan are pre-modern myths. When we go to that extreme, we let evil operate unchecked. We don't ask for the Spirit's help in giving us the mind of Christ (1 Cor. 2:16) because we actually believe our thinking isn't susceptible to evil influence.

Perhaps one of the most damaging consequences of our assumption that thoughts are neutral is the self-loathing and depression that accompany our failures to keep harmful thoughts at bay. When we can't get a thought to leave us alone, when it keeps coming back like a moth to a flame, we start to drift into self-loathing. We doubt our own faith, our Spirit-given power to repel evil because of the completed work of Christ.

That makes sense, doesn't it? If demons and the spiritual forces of evil, all those "principalities and powers," don't exist, or at least have no bearing on our thought life, then we're the only ones to blame. Every nagging thought is our fault. Self-loathing is the natural consequence.

Don't misunderstand me. There are plenty of thoughts that result from indwelling sin. The Spirit will be purging us of those thoughts for the rest of our lives. There are plenty of things between the walls of our head that are our fault. But we need to balance that truth with the biblical teaching that evil is real, and that thoughts can be evil. When we deny that possibility, we're leaving the door open for Satan to work undetected. If some of Satan's best work is done not by putting things into our minds but by keeping things out, then we need to let this truth in: thoughts can be evil, weapons of the devil to draw us further from God, deeper into doubt, and lower in self-absorption.

Combatting Evil Thoughts

How do we combat evil thoughts? We kill them. Sorry if that sounds too forward. But that's the only way. We kill evil thoughts with powerful truth. More specifically, we rehearse hand-selected Scripture whenever the evil thought approaches. The word of God isn't just a conceptual comfort; it's a cutting blade. It cuts through evil. When we're struggling to fight a particular thought, we need to confront that thought with the power of the truth. If thoughts can be evil, then they can also be wise and righteous; they can be Christ-exalting.

The word of God isn't just a conceptual comfort; it's a cutting blade.

Do you have evil thoughts that seem to follow you around? Pray that the Spirit would lead you to the passage of Scripture you need to rehearse when it approaches. And lean on the body of Christ for support. Have others pray for you as well. I'm old enough now to realize that nothing good seems to happen apart from prayer. We disregard the power of prayer almost as much as we disregard the presence of evil in our thought life. And that's a tragedy. Prayer is likely the very thing that will win our battles, now that Christ has won the war.

May we take every thought captive to Christ (2 Cor. 10:5). And may we lean on the power of God in his word to destroy the evil thoughts trying to rob us every hour.


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