Third Sunday after Trinity June 20, 1999


Jesus Keeps 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 of His people, dear fellow believers in Him, dear fellow redeemed.

My parents live in a growing suburb, just south of the Twin Cities. This particular community seems to bustle with more people each year, more traffic on the streets, more houses under construction. But you would never know, if you merely drove by their house. The driveway comes out to a gravel road, not a paved street. The neighbors are no closer than 200 yards away, completely hidden from sight by a few hills and lots of trees. It’s a rather secluded location that my dad fell in love with, when he bought the place 20 years ago. Yet he would be the first to admit: his secluded home site has a serious downside. On two different occasions thieves came when they were gone, broke into the house at night, and stole various items of value. After the second break-in my dad was convinced. It was time to install a home security system. Since then, the burglars have stayed away.

I don’t suppose that security alarms are a big necessity here in Jamestown. Maybe some people feel the need to own one. They do tell us to put smoke alarms, even CO2 detectors in the house. Carbon monoxide 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 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 has a similar approach with His family, His people, the sheep of His flock. The Good Shepherd has installed a “security system” for you and me. As we learn from our text,

Jesus keeps you safe from error.

Here’s the plan …

  1. He shows you the danger of false teachers.
  2. He helps you identify the error of false teachers.
  3. He also 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 congregations. I’ve heard people say, “Oh, a little error is not so bad, as long as people stick with most of the truth.” That’s not what Jesus said. He tells you plainly, “Beware of false prophets.” When you hear this command, don’t think of it as another rule that places another restriction in your life. It’s not like the “No Trespassing” sign that people use to keep you out of their property. It’s more like the tornado warning that you hear on the radio. The Lord is trying to keep you safe. He doesn’t want you to lose your hold on the truth or wander in confusion or, even worse, to lose your faith in Him. He gives 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 here’s the key point: 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, if we only go by outward appearances. The false teacher does not come with a name tag, which says “I’m a false prophet. Stay away from me.” 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 would be the Mormon missionary. He’s out on the street, knocking on doors, talking to folks like you and me. He’s polite, humble, dedicated to his work. Admirable qualities under normal circumstances. If he lived next door to you, he would be an excellent neighbor. When he speaks, the words sound right. He talks about Jesus, salvation, faith. He quotes the Bible. He belongs to this well-established religious group with the name, “Church of Jesus Christ of Latter Day Saints.” It all looks good on the surface. But we 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.

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 middle of the true-teaching Christian church. We have to be on guard not only from those outside the fellowship, but possibly from those within. 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 not from the person, but from the error that he teaches.

Let’s talk about the word “error” for a moment. I say “error,” and maybe you think “mistake.” The shortstop makes an “error” in the field. A student makes an “error” on a test. A business makes an error on a bill. Well, that’s a big deal, isn’t it? If they make an error on your bill, it might cost you money. Error causes 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 be an example—to show us how to live a good life and earn our favor with God. Now think: if we were to follow through with that teaching and believe it as our hope and confidence, that would surely cost us our salvation.

That is finally where every error will take you. It may start out small; it may seem insignificant at first. But the so-called “little error” does not stay little. It grows. It spreads, like yeast through the dough, like cancer through the body. The one error will multiply into many more false teachings that ultimately corrode and destroy the vital teaching, the Gospel, the truth that we are saved by Christ alone.

That’s why Jesus warns you. He doesn’t want you or any other believer to lose 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. He wants you and your children and your grandchildren to know that salvation is free through Him. Heaven is a gift that God gives away, without any contribution or payment from us. That message is too precious, too vital to let it be watered down or contaminated by the corrosion of doctrinal error.

Let’s understand the usual chain of events. Every error of false teaching comes from the devil, not from God. It will come in the form of a message, distributed and defended by human messengers. It will come in different shapes and sizes. It will generally sound good to human reason. Therefore it will gain many followers among your friends, neighbors, and co-workers. False teaching will have its own success according to the devil’s plan—confusing the heart, deceiving the mind, destroying people’s faith. It looks like a grim picture. Thankfully, we can say that all is not lost. Jesus has a plan to keep us safe. He helps us to recognize the error of false teachers.

It’s reassuring … what He says 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 “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 to the core, spoiled “fruit” from a decayed and dying “tree.” That tells you something. We should not go to the false prophet, expecting to gain some good fruit mixed in with the bad. “The bad tree cannot bear good fruit,” Jesus said. Which means that we cannot selectively pick and choose the truth from the error. The only way to avoid the “bad fruit” of false doctrine is to avoid the “bad tree,” the ministry of the false teacher.

In the grocery store there are certain ways to check the quality of a cantaloupe. The same goes for the fruit of those who teach religious doctrine. We test. We grade. We examine. School teachers have an answer key to help them grade the work of their students. Christ gives us His Word as the “answer key” to grade the doctrine of pastors, religious literature, traveling missionaries, the doctrinal platform of church bodies, including our own CLC. The grade will not be A to F. It’s either “pass or fail.” We compare the teaching in question with the Word of God. If the teaching agrees with the Bible in every point, it will pass as the truth. If the teaching disagrees with the clear statements of God’s Word, it will fail. We need to recognize that. We need to reject the error as a hazard to our spiritual health.

Jesus said, “By their fruits you will know them.” He said it twice. He’s showing you the key to success, the key to security. And not only through His instruction. Isn’t He the one who makes the difference in the hearts and minds of His people? He sends the Holy Spirit to build up our knowledge of the truth and our faithfulness to the Word. How else could it be? Our security from error could never depend on the efforts that we make. The Lord 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 or security alarms. Because they are designed by man, they are not fool-proof. But the Lord’s plan to keep us safe from error—that plan 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 of God be the determining factor, the overriding authority in every matter of doctrine, then the error cannot even begin to lead us astray. The only way that error could get the better of us is if we let it happen, if we fail to use the safeguard of God’s Word. The Lord has promised: “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, the apostle said: “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 world in which we live. Jesus Himself predicted: “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 safe in the path of truth. At the same time He reassures us that the trouble we have with error is only temporary. Every false teaching has an expiration date. Christ will silence the voice of false teaching once and for all on Judgment Day.

Christ will get the last word, not Satan. Jesus will pull the plug according to His promise: “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 will judge the people who are responsible. He will judge them in their rebellion and their unbelief.

We tend to play down this discussion of truth and error. We become indifferent to the problem that we face. On the other hand, I don’t want to imply that we are overwhelmed and overmatched. Certainly we are 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 and avoid them. Finally, He brings all the deception to an end. For the time being, we are like the soldier in the heat of battle. We have to be careful and alert. We need to rely on the weapon God gives, the power and the truth of His Word. But the battle is not ours to fight alone. With Christ on our side, the enemy has to surrender. The side of truth will eventually win. Jesus does more than keep you safe. He leads you to victory—the victory of truth, the victory of faith, the ultimate victory of life everlasting. Amen.

—Pastor Steven Sippert

Our Savior’s Lutheran Church
Jamestown, North Dakota

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