“Readers are advised to remember that the devil is a liar.”

So warns C.S. Lewis at the beginning of Screwtape Letters (ix). The warning is apt not only for readers of Lewis’s modern classic, but for all people, everywhere, all the time. No matter how alert we are to spiritual warfare, we are advised to remember that the devil is a liar.

We can hardly remember too often. For, as long as we are in this world, something within us — “deceitful desires” (Ephesians 4:22) — will want to believe him. Something within us will want to believe him when he suggests that freedom lies just over the fence of God’s commands. Or that sin holds something essential to our happiness. Or that obedience to God will make us miserable.

All lies, of course. But under the sway of sin’s deception, the devil’s whisper can sound like gospel truth. Therefore, our peace and security, our happiness and holiness, depend on being able to say with the apostle Paul, “We are not ignorant of his designs” (2 Corinthians 2:11).

Devil’s Designs

To be sure, we cannot trace every lie directly back to the devil. Sin has its own native deceitfulness (Hebrews 3:13). But all lies in this world bear the mark of him who is “the father of lies” and “the deceiver of the whole world” (John 8:44; Revelation 12:9). Study the father’s face, and you will learn to recognize his brood.

What do we see when we examine the devil’s designs? We see that he lessens the guilt of sin, hides the danger of sin, and embellishes the pleasure of sin.

Guilt Lessened

When the devil met our Lord in the wilderness, he sought to make sin seem small. If Jesus truly were the Son of God, what harm could there be in turning this one stone into a loaf, or in allowing the adoring angels to bear up his falling body (Matthew 4:3–6)? Surely, given the circumstances, these were privileges and necessities, not sins.

Now, we are not the Son of God. But the devil knows a thousand ways to suggest the same to us. Perhaps we hear, “You’re so tired and under such pressure; who can blame you?” Or, “Did you not see so-and-so do the same just last week?” Or, “If you are God’s child, grace is available.” Slowly, the blackness of sin turns gray, God’s commands become recommendations, and before we even give way, we are mixing a balm to soothe our wounded conscience.

Danger Hidden

When God describes our temptations, he often uses imagery of predator and prey, of hunter and victim. Sin ushers us into “a snare of the devil” (1 Timothy 3:7); likewise, the iniquities of a wicked man “ensnare him, and he is held fast in the cords of his sin” (Proverbs 5:22). Of course, “in vain is a net spread in the sight of any bird” (Proverbs 1:17), so the devil carefully hides the net from view.

Though God has warned a thousand times concerning the fruit of forbidden sin — that “in the day you eat of it you shall surely die” — the devil never tires of telling Adam’s children, “You shall not surely die” (Genesis 2:17; 3:4). “No, no,” he says. “What danger could there be in one small sin? Find relief this once, gratify your flesh this once, answer the voice of your passions this once, and then return to righteousness.”

With such words, he covers the hook with the worm, and brushes leaves and branches over the net prepared to snap.

Pleasure Embellished

All temptation would be harmless, of course, if sin promised no pleasure — if the net offered no meal, and the hook no worm. So the devil takes what fleeting pleasures there are in sin and makes them feel, for the moment at least, sweeter than the pleasures at God’s right hand.

Under the force of Satan’s temptation, Cain feels the thrill of revenge; Achan, the glory of wealth; David, the delight of adultery. We too may find ourselves fixed on a certain sin with an overwhelming sense of necessity: if we don’t click here, buy this, drink that, how will we be happy? How will we endure our sufferings or our boredom? Perhaps we would repress some essential part of us. Perhaps, having gone this far, we have no choice but to plunge headlong.

All the while, the light of God’s face grows dimmer, the narrow way squeezes, and the commandments of God, which once brought so much freedom, fall upon us with a weight we cannot bear.

‘We Are Not Ignorant’

Such are some of Satan’s designs. Now, what must we do to be able to say with Paul, “We are not ignorant” (2 Corinthians 2:11)? We must saturate ourselves so thoroughly with “the truth . . . in Jesus” (Ephesians 4:21) that, in the moment of temptation, the guilt of sin is exposed, the danger of sin is revealed, and the pleasure of sin is redirected.

Guilt Exposed

When the devil suggests, “This sin is just a small one,” Scripture trains us to respond, “There is no such thing as ‘a small one.’ Is it a small thing to indulge the sin my Savior died to forgive? Is it a small thing to drag an idol into the temple of the Holy Spirit (Ephesians 4:30)? Or could it ever be a small thing to dismiss my Father’s words as empty talk?”

Or when he whispers, “But God is merciful,” we say, “Yes, God is merciful — not only to forgive me, but to purify me as well. Mercy, grace, and pardon do not tempt me to sin; they train me for godliness (Titus 2:11–12). Do you not remember that the kindness of the Lord is a summons to repent (Romans 2:4)?”

Or when we hear, “But you’ve been under so much pressure,” we answer, “But pressure can never excuse despising God’s commands. Can I sincerely imagine standing before the judgment seat of Christ (2 Corinthians 5:10), holding my bitterness, self-pity, or anger, and saying, ‘I was under so much pressure’?”

Danger Revealed

As the Spirit exposes the guilt of sin, he also reveals its danger. When we find ourselves enticed by the logic of “just this once,” we remember that the fisherman needs only one bite to catch his fish; the hunter needs only one foot to release the trap. Likewise, the devil needs only one indulgence to tighten his grip on our souls. Drinking too much “just once,” looking at pornography “just once,” gratifying our vanity “just once,” apart from a decisive act of repentance, will leave us changed.

John Owen writes, “Some, in the tumultuating of their corruptions, seek for quietness by laboring to satisfy them, ‘making provision for the flesh, to fulfil the lusts thereof,’ as the apostle speaks. . . . This is to aslake fire by wood and oil” (Indwelling Sin, 178). In other words, trying to silence our sinful desires by giving in “just this once” is like trying to put out a fire by adding another log.

Pleasure Redirected

The battle is not yet over once sin’s guilt is exposed and its danger revealed. Our God-given desire for pleasure, forceful as the Niagara, cannot be dammed through mere self-denial. The river must run somewhere — and if not to sin, then to something better.

Here, many of us run into trouble. The pleasures of sin are often immediate, while the pleasures of righteousness are often delayed. The pleasures of sin require no self-denial, while the pleasures of righteousness sometimes require cutting off a hand (Matthew 5:30). How can we deny ourselves the easy and immediate for the difficult and delayed?

The same way a hiker, desperate for water, denies himself a saltwater puddle because he knows a crystal stream runs two miles up the path. He remembers not only that the puddle will enrage his thirst all the more, but also that God has supplied water far sweeter if he will only keep walking. So, with “the assurance of things hoped for” bidding him onward (Hebrews 11:1), he sets his face toward the path.

Every temptation, then, is an opportunity not only to reject the fleeting pleasures of sin, but also to embrace the surpassing worth of Christ. Every temptation offers a chance to shame the devil, not by mere self-denial, but by a better satisfaction: Christ himself, who promises pleasure we can scarcely imagine — and who never lies.