Matthew 7:15-23

In the name of Jesus. Amen.

We live in a dangerous world. Because sin and death have entered God’s good creation, there are all sorts of things that can harm you. You could get hit by a drunk driver on the way home. A lunatic could shoot and kill you at the grocery store. Smoke from wildfires can do damage to your lungs. An asteroid could fall from the sky. But Jesus doesn’t tell you to beware of any of those things. The reason Jesus doesn’t warn you about those things isn’t that He is naïve and thinks they are harmless. Rather, He doesn’t warn you about them because they can only temporarily harm you. Christ does warn you—and it’s a stern warning—against false prophets.

Don’t get the wrong idea about these false prophets. A prophet isn’t only someone who predicts the future. Isaiah, Jeremiah, Ezekiel, and Daniel were all prophets who spoke accurately about things that were still in the future. King David was a prophet when he wrote about Christ’s death, resurrection, and rule in many of the Psalms. They did that because they were inspired by the Holy Spirit to declare God’s Word. And sometimes, that Word dealt with things that were still to come. But the Bible also gives the title of prophet to those who publicly preach and teach God’s Word (Act. 15:32; 1 Co. 14:1, 3, 29-32). That is what Jesus is referring to here when He warns against false prophets. They are people who preach and teach God’s Word, but they do it falsely.

Jesus describes these false prophets as ravenous wolves who dress up in sheep’s clothing. It’s a stern warning. It’s a solemn warning. It’s right up there among the most dire warnings that Jesus speaks in all of Scripture. As serious as this warning is, we should find comfort even in the warning. Let me explain that first, then we’ll get to the warning.

Imagine you were sick. You’re in pain. Your strength keeps declining as you become more and more lethargic. Your body is slowly shutting down. You’ve tried all sorts of things, but none of them work. Doctor after doctor can’t figure out what’s wrong. You know that if this sickness keeps progressing, it’ll kill you. Imagine you finally went to a doctor who had the answer. He diagnoses your illness perfectly, gives you a prescription, and it works. After the first dose, the sickness is gone. Your energy returns. You get back to normal. You go back to that doctor for a follow-up.

He is pleased after he looks at your vitals, sees how well you’re doing, and is delighted. Then the doctor’s face becomes utterly serious. He looks intently at you and says, “Listen to me. Don’t ever stop taking this medicine. Never miss a single dose. Take it exactly as I’ve prescribed it to you. If you ever stop taking it, you’ll die. If anyone tries to tell you about another remedy, they’re wrong. This is the only cure. I’ll always make sure you have it for free. No cost to you ever, but you need to keep taking it.”

Now, would that warning from the doctor be good or bad news? Of course it’s good news. There’s medicine that keeps you healthy, and it’s free. That’s the way we should hear Jesus’ warning against these false prophets. Yes, it’s a stern, sober warning. But it also means that there are true prophets and shepherds who give the medicine of immortality for free.

As you receive the free medicine of the Gospel, beware of false prophets. Beware of the ravenous wolves who would lure you away from this Gospel. They are the most serious danger you face, Christian.

Jesus tells you why they’re dangerous. Sure, Jesus calls them ‘ravenous,’ but that isn’t what makes these wolves a threat to you. The danger isn’t in their sharp teeth and powerful jaws. It isn’t their speed and strength. No, the wolves Jesus warns against are strange. They are odd wolves.

This might sound a little silly but, as I studied this text this week, I kept thinking of children’s stories. I first thought about “The Three Little Pigs.” In that story, the wolf is dangerous because he huffs, puffs, and blows the houses of straw and sticks down. I don’t know for sure, but I don’t think wolves are known for their lung capacity. That wolf at least warns before he comes after the pigs.

Then I thought of “Little Red Riding Hood.” In that story, the wolf doesn’t barge in the door or announce himself with a roar. Instead, he puts on the grandmother’s nightgown, pulls the cap over his ears, softens his voice, and climbs into the bed. For Little Red, the most dangerous thing in the room looked and sounded like the safest person she knew.

That’s the kind of wolf Jesus warns about here. What makes these wolves dangerous is their deception. They come disguised in sheep’s clothing. The wolves who will destroy you look like sheep. They sound right. They will talk about Jesus. They can quote the Bible. They may even do mighty works in Christ’s name (Mt 7:22). The danger is not their strength. The danger is their clothing. 

If these false prophets came to you and looked like a wolf, you would run. If they came preaching open blasphemy, you would barricade the door. But that’s not how they come. They come dressed as a Christian teacher. They appear with a Bible in their hand and a smile on their face. These false prophets come saying things that sound almost right. That is how they get into the house.

Jeremiah warned about the same thing centuries earlier in our Old Testament reading (Jer. 23:16-29). The false prophets of his day did not stand up and say, “Forget about Yahweh,” or, “Follow these other gods.” No! They sounded nice. They softened God’s Law. They proclaimed false things to sinners. “Everything will be fine, and no disaster will come upon you” (Jer 23:17). They spoke visions of their own minds and called it the Word of the Lord. They filled the unrepentant people with false hopes and false comforts. And, sadly, the people listened, because the message felt safe, soft, and comforting. Like a grandmother’s voice. We face the same deception.

But Jesus tells us how to spot the difference. Christ gives us one test: “You will recognize them by their fruits” (Mt 7:16). You don’t recognize them by their personality, by how nice they are, or even by whether they can quote Scripture. Remember, the devil himself used Scripture when he tempted our Lord in the wilderness (Mt. 4:1-11).

According to Jesus, you spot these false prophets by their fruits. The fruit of a prophet is his teaching—just like the fruit of a baker is the bread he bakes, or the fruit of a doctor is the healing he brings. For anyone who prophesies—anyone who proclaims God’s Word—you have to ask two questions: First, “Does this point out where I have sinned? Does it faithfully proclaim that I am a sinner in need of God’s grace and mercy?” Or, “Does this tell me that God loves me and others just the way we are without any repentance?” The second question to ask is, “Does this point me to Christ crucified and risen, freely, without my works?” Or, “Does this put the weight back on my shoulders? Am I being told that my salvation depends on me putting in a little more effort or sincerity or a few more good works?”

Jesus says that a healthy tree cannot bear bad fruit, and a diseased tree cannot bear good fruit (Mt 7:18). In other words, the teaching will eventually show itself. But you need to know the real thing well enough to compare.

That is why Christ keeps driving us back to the Scriptures. That is why studying the Bible is not just some optional busy-work. You can’t turn off your ears and mind the moment a sermon starts. Jesus is calling you to be fruit inspectors. Not because you are smarter than everyone else, but because the wolves are that good at disguise.

God’s Word doesn’t always flatter you. It doesn’t always say, “Peace, peace,” because there isn’t always peace (Jer. 6:14; 8:11; Ezk. 13:13). Scripture isn’t always pleasant. It isn’t always what you want to hear. God’s Word kills our old, sinful nature so that it can make us alive. It shows you the wolf and then points you to the only refuge—Christ Himself.

Whenever someone claims to proclaim God’s Word, be suspicious. Watch for red flags. That discernment is a good work that Jesus gives you to do today and every day.

Be wary of every teacher and preacher—including the one standing in this pulpit. Don’t just trust me because I’m so smart, handsome, and friendly. (I’m not much of any of those things.) Test the teaching. Compare it to the Scriptures. Hold fast to God’s Word. See the goodness of His Law. And cling to the Gospel—the full, free forgiveness of sins that the Gospel delivers to you. Build on that.

The wolves are always out there in their soft, wooly, sheepish disguise. But the Good Shepherd has already laid down His life for you, His sheep. His voice, His Word, is what will keep you safe now and for eternity. Amen.

The peace of God, which surpasses all understanding, will guard your hearts and minds in Christ Jesus (Php. 4:7). Amen.