When we are thinking rationally, we can see the insanity of sin. Why would anyone throw away a livelihood, a family, or a reputation for a 30-minute roll in the hay? What good will it do to seek revenge, and feel satisfied for an afternoon, if it means reaping a whirlwind of consequences for decades? Why would we keep drinking, telling ourselves it’s only in moderation, if we know a thousand bad things can happen if we fall off the wagon again? Why would we flirt with a married man? Why follow the woman up to her room? Why flip through those channels in the hotel room?

The Puritans use to speak of the exceeding sinfulness of sin. And they were right to do so. Sin is a heinous insult to a holy God. It is lawless, treasonous, rebellion.

It’s also really dumb.

Everyone who knows the Bible, knows people, or knows his own heart, knows this to be true: sin makes us stupid.

Think of the Garden of Eden. You literally live in paradise, and you listen to a snake whisper something about a tasty fruit. Why risk it?

Or David and Bathsheba. You are the king for crying out loud. You have everything. You’ve seen the Lord bless your socks off since you were a boy. And you send for a pretty bathing girl? And then try to cover your tracks with one boneheaded sin after another?

The prodigal son is another classic example. He could have had fine food, familial warmth, and a roof over his head. But he got greedy, blew through a wad of cash, and ended up with the pigs.

Or what about the thief on the cross (the bad one) who can’t think of anything better to do with his final breaths than to mock another dying “criminal”?

And then there’s Ananias and Sapphira who get themselves killed over a silly lie about how much they got for their property. What a waste.

Sin makes us stupid.

When we are thinking rationally, we can see the insanity of sin. Why would anyone throw away a livelihood, a family, or a reputation for a 30-minute roll in the hay? What good will it do to seek revenge, and feel satisfied for an afternoon, if it means reaping a whirlwind of consequences for decades? Why would we keep drinking, telling ourselves it’s only in moderation, if we know a thousand bad things can happen if we fall off the wagon again? Why would we flirt with a married man? Why follow the woman up to her room? Why flip through those channels in the hotel room?

Sadly, we’ve all seen it before. From friends and family. Maybe from a trusted pastor or ministry colleague. It’s easier to see in others—the defensiveness, the blame-shifting, the excuse making, the nonsense of exchanging decades of faithfulness for minutes of folly. But what’s clear when looking at others can be hard to spot in ourselves. Just like the proverbial piece of lettuce on the lips, we can be last to realize how stupid we’ve become because of sin.

We may sin in serenity for a season. But God cannot be mocked forever (Gal. 6:7). Our madness will be made manifest. Eventually, his words will overtake us (Zech. 1:6).

So repent, says the prophet (Zech 1:6). Let us turn from temptation before it is too late. Let’s all of us—myself included—hide the Word in our hearts, or better still, tell a friend, “Please tell me when I’m being stupid, and if I don’t believe you then, remind me that I believe you now.”

And if we ever do find ourselves sitting among the swine, let’s remember that the Father is ready for us to come home. With open arms, a warm embrace, and a top-notch party.

When we come to our senses and put aside the stupidity of sin.

Kevin DeYoung is senior pastor of Christ Covenant Church in Matthews, North Carolina. Kevin blogs at the Gospel Coalition; this article is used with his permission.