Thirteenth Sunday after Trinity September 6, 1998


The Shepherd’s Plan to Keep You Safe from Error

Matthew 7:15-23

Beware of false prophets, who come to you in sheep’s clothing, but inwardly they are ravenous wolves. You will know them by their fruits. Do men gather grapes from thornbushes or figs from thistles? Even so, every good tree bears good fruit, but a bad tree bears bad fruit. A good tree cannot bear bad fruit, nor can a bad tree bear good fruit. Every tree that does not bear good fruit is cut down and thrown into the fire. Therefore by their fruits you will know them. Not everyone who says to Me, ‘Lord, Lord,’ shall enter the kingdom of heaven, but he who does the will of My Father in heaven. Many will say to Me in that day, ‘Lord, Lord, have we not prophesied in Your name, cast out demons in Your name, and done many wonders in Your name?’ And then I will declare to them, ‘I never knew you; depart from Me, you who practice lawlessness!’

In the name of Christ Jesus, the Good Shepherd, who watches over the security and the welfare of His sheep, dear fellow believers in Him, dear fellow redeemed.

My parents live in a growing suburb, just south of the Twin Cities. This suburb is bustling more and more people each year, more and more traffic on the streets, more and more houses being built. But you would never know these things by looking at the road on which they live or observing the land near their house. The driveway comes out to a gravel road, not a paved street. The next door neighbor is 300 yards away, completely hidden from sight by trees and hills. It’s a rather secluded location that my dad fell in love with, when he bought the place nearly 20 years ago. Yet this secluded location has a serious downside. On two different occasions thieves broke into the house and stole their stereo and other items of value. The break-ins were enough to coax my dad into buying a home security system. Since then, the burglars have stayed away.

Now security systems are not a big necessity here in Valentine. But they do tell you to have a smoke alarm in your house, perhaps a CO2 detector. Carbon monoxide is a deadly gas that will kill people if it’s not detected with adequate warning. We live in a world where people and things around us can do us serious harm, if we don’t have a way to identify the danger and take the necessary precautions. Out of loving concern for your family, you put a smoke alarm in the bedroom of your children. Well, Jesus had a similar approach with His family, His people, the sheep of His flock. The Good Shepherd has established a “security system” for you and me. As we learn from our text in Matthew, it’s the

Shepherd’s plan to keep you safe from error.

  1. He shows you the danger of false teachers.
  2. He helps you identify the error of false teachers.
  3. He promises to silence the false teacher once and for all on Judgment Day.

We tend to underestimate the problem that error will cause for believers and Christian congregations. I’ve heard people say, “Oh, a little error is not so bad.” That’s not what Jesus said. He tells you plainly, “Beware of false prophets.” This urgent command is not a test of your loyalty. It’s not like the “No Trespassing” sign, which tells you to keep out of somebody else’s property. It’s more like the tornado warning that you hear on the radio or see on the Weather Channel. When Jesus says, “Beware of false prophets,” He’s alerting you to danger. He’s trying to keep you safe. He doesn’t want you to lose your hold on the truth or wander in confusion or lose your faith in Him. He speaks His warning because He cares so much. It’s the main reason why He shows you the danger of false teachers.

The false teacher, or false prophet, is simply a person who claims to speak for God either as pastor or missionary or avid follower, but the revelation or the teaching that he brings is not from God. This person will teach error as though it were the truth of God Himself. Unfortunately, the false teacher can be hard to recognize, based on outward appearances only. The false teacher does not come with a name tag, telling you that he’s a false prophet working to deceive you. Like Jesus said, “Beware of false prophets, who come to you in sheep’s clothing, but inwardly they are ravenous wolves.

Don’t be fooled by the outward appearance. The false teacher, in many cases, will act like the Christian is supposed to act. His outward life will have the appearance of morality and virtue. An excellent example of this would be the Mormon missionary. When he’s out on the street, knocking on doors, talking to folks like you and me, he’s polite, humble, and dedicated to his work. Admirable qualities under normal circumstances. If he lived next door to you, he would make for an excellent neighbor. Even his words sound good at first. He talks about Jesus, and faith, and the Bible. He belongs to this well-established religious group with the name, “Church of Jesus Christ of Latter Day Saints.” But you shouldn’t be fooled by the outward appearance. He’s not a shepherd that Jesus sent to lead you to the cross. He’s a wolf in sheep’s clothing, a danger to your spiritual health.

I believe the Mormon missionaries are busy in the area right now. They’re dedicated to the cause of building up their membership with more and more people. They are generally quite sincere in what they believe. They probably don’t realize the trouble that they’re causing or the damage that they’re doing. But that does not change the fact that they are dangerous. Because of the false teaching that they bring, they have become, in effect, the tools of Satan. It has to be the devil working, sending them out to confuse, deceive, weaken, and destroy the faith of those who belong to God.

Of course, the Mormon missionary is just one example. False teachers rise up in plenty of other groups. In fact, the false prophet can rise up right in the midst of the true-teaching Christian church. We have to be on guard from within and without. John tells us in his First Epistle, “Beloved, do not believe every spirit, but test the spirits, whether they are of God; because many false prophets have gone out into the world.(1 John 4:1) The false teachers are out there. In some cases, they look like Christians. They might even be Christians, who belong to churches that teach many of the same doctrines that we believe. The devil has disguised them well, making it even harder for us to detect the danger, which comes from the error that is taught.

Let’s explore the word “error” for a moment. I say “error,” and maybe you think of “mistake”—something wrong, an error on a test, or maybe an error on a bill. Well, that’s a big deal, isn’t it? If people make an error on your bill, it could cost you money. Error causes serious problems, especially in the matter of Christian doctrine. Everything that we learn about God has to be true to the Bible. Otherwise, our faith is based on shaky ground. Let’s say that people teach the idea that Jesus has come to show us how to live a good life and earn our favor with God. If we were to believe that teaching, it would surely cost us our salvation.

Finally, that’s where every error is leading. It might start out small; it might seem insignificant at first. But the so-called “little error” doesn’t stay little. It grows. It spreads, like yeast throughout the dough, like cancer throughout the body. The one error will multiply into many more false teachings that ultimately corrode and destroy the vital teaching, the Gospel truth that Jesus Christ is our only Savior from sin.

That’s why Jesus warns you. He doesn’t want you or any other believer to lose the truth of the Gospel. There’s too much at stake. Jesus paid too dearly to let us be misled. He wants you to know for a fact that He has died for all your sins and made you right with God now and forever. He wants you and your children and your grandchildren to know that salvation is free through Him, that heaven is a gift that God gives away, without any effort or contribution or payment that we make. That Gospel message is too precious and too vital to let it be contaminated or diluted by the corrosion of doctrinal error.

Please understand the typical chain of events. The error of false teaching will start with the devil himself. Error will come in the form of a message promoted and defended by human messengers. It will come in different shapes and sizes. It will sound good to human reason and gain many followers among our friends, neighbors, and co-workers. False teaching will succeed in doing what the devil sent it to do: to confuse the heart, deceive the mind, and destroy the faith of believers. Thankfully, we can say that all is not lost. Jesus has a plan to keep His people safe. He helps us to recognize the error of false teachers.

It’s a reassuring thing that we find in our text: “You will know them by their fruits. Do men gather grapes from thornbushes or figs from thistles? Even so, every good tree bears good fruit, but a bad tree bears bad fruit. A good tree cannot bear bad fruit, nor can a bad tree bear good fruit.” When Jesus talks about “fruit” in this part of the Bible, it’s not the same as the “fruits of faith.” The fruit of the false prophet has to be his teaching, not the way he lives his life. And notice: the fruit of the false teacher is not fit for human consumption. It’s rotten “fruit” from a decayed and dying “tree.” That tells you something. We should not go to the false prophet, expecting some good fruit mixed in with the bad. “The bad tree cannot bear good fruit.” It’s a forceful statement that Jesus makes; it’s a clear warning. We cannot selectively pick and choose the truth from the error. We avoid the “bad fruit” of false doctrine only by avoiding the “bad tree,” the false teacher and his ministry.

Just the other day I was talking to Amy about the fruit we buy in the grocery store. There are certain things you can check to determine the quality of a cantaloupe, for instance. The same goes for the fruit of those who teach religious doctrine. We apply the test of Scripture. School teachers have an answer key to help them correct and grade the papers of their students. Christ gives us His Word as the “answer key” to examine and grade the doctrine that pastors or missionaries or churches profess to believe. And believe me, there are only two possible grades. It’s either “pass or fail.” We compare the teaching in question with the Word. If the teaching agrees with the Bible, it will pass as the truth. If the teaching disagrees with the clear statements of God’s Word, that teaching will fail. We have to reject it as error.

Jesus said, “By your fruits you will know them.” He said it twice—verses 16 and 20. It’s a reassuring thing to hear. Jesus makes the prediction that believers will recognize the error of false prophets. That prediction is not merely based on His knowledge of the future. It’s based on His power and His promise. He will guide us to apply His Word correctly. The Holy Spirit will work His positive influence and lead us to know the truth and defend the truth. How else could it be? Our security from error could never depend on the effort that we make. The Shepherd has to work on us from the inside out.

Of all the protection plans that we use, this one is guaranteed. You can’t say that about insurance coverage or security systems. They are not fool-proof in every single case. But the Lord’s plan to keep us safe from error is airtight; it does not have a chink in the armor. As long as we follow the instructions, as long as we let the Word be the overriding authority in every matter of doctrine, then the error cannot enter in and take root among us. The only way that error could get the better of us is if we let it happen. The Shepherd has given His promise to all the believers, “If you abide in My word, you are My disciples indeed. And you shall know the truth, and the truth shall make you free.(John 8:31-32)

As we live in this world, we have to be on guard. For your own good, the Lord directs you to “test the spirits.” To keep us safe from error, Jesus says, “Note those who cause divisions and offenses, contrary to the doctrine which you learned, and avoid them. For those who are such do not serve our Lord Jesus Christ, but their own belly, and by smooth words and flattering speech deceive the hearts of the simple.(Rom. 16:17-18) The danger of deception will continue to exist as part of the sinful environment in which we live. Shortly before His death, Jesus said, “Many false prophets will rise up and deceive many…. False christs and false prophets will rise and show great signs and wonders to deceive, if possible, even the elect.(Matt. 24:11, 24) Thank God, it’s not possible to deceive the elect. Jesus keeps us in the path of truth. At the same time He reassures us that the trouble we have with error is only temporary. The problem of false teaching has an expiration date. Christ will silence the false teacher on Judgment Day.

Christ will get the last word, not Satan. Jesus will pull the plug and end this troublesome reign of error. “Many will say to Me in that day, ‘Lord, Lord, have we not prophesied in Your name, cast out demons in Your name, and done many wonders in Your name?’ And then I will declare to them, ‘I never knew you; depart from Me, you who practice lawlessness!’” Not only will He bring the influence of false teachers to an end. He promises to judge those people in their rebellion and their unbelief.

Now the pending judgment of these men should not leave us feeling smug or superior. We need Christ and His Word to keep us from following the error that sounds so good to human reason. I need Christ and His Word to keep me as a faithful shepherd. I can’t be a teacher of the truth unless the Teacher Himself does His work, backing me up, replenishing and fueling the ministry that He gave me in the first place.

This discussion of truth and error is more serious than we often realize. But we can still take heart. We are certainly under fire, but we are not overcome. Jesus keeps you safe. He alerts you to the danger of false teachers. He leads you to identify the errors that they teach. And finally, He brings all the deception to an end. In some ways you are like the soldier in the heat of battle. You have to be careful and alert. You have to rely on the weapon God gives you, the power and the truth of His Word. But the battle is not yours to fight alone. With Christ on your side, the enemy has to surrender. The side of truth will eventually win. The Shepherd will not only keep us safe from error. He will lead us to victory—the victory of truth, the victory of faith, and the ultimate victory of life everlasting. Amen.

—Pastor Steven Sippert

Our Savior’s Lutheran Church
Jamestown, North Dakota

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