The Necessity of Pure Doctrine

Trinity 8| Matthew 7:15-23| Pastor James Preus| Trinity Lutheran Church| July 25, 2021 

Is pure doctrine important? Our Lord Jesus sure thinks it is. He tells us to beware of false prophets. What is a false prophet? A prophet is someone who speaks for God. A false prophet is someone who claims to speak for God, but rather tells lies. The Lord spoke through the prophet Jeremiah saying that the prophets have prophesied lies in his name (Jeremiah 23). This is why Jesus says that they come to you in sheep’s clothing, but inwardly are ravenous wolves. That is to say, they come to you with the appearance of someone you can trust, but that is only a disguise. Rather, their intent is to destroy you. They come to you looking like a trusted pastor, calling themselves Christian, and minister. They prophesy in Jesus’ name, cast out demons and do many mighty works in Jesus’ name, but they do not do the will of God. They are liars, which means they do the will of the devil, who is the father of lies.  

The word doctrine means teaching. Pure means unpolluted. Pure water does not have any dirt or harmful chemicals in it. Pure gold does not have dross. It shouldn’t be difficult to understand that you should desire to learn pure doctrine and to mark and avoid false doctrine. Pure doctrine comes from Jesus Christ, who is the only way to heaven. False doctrine comes from Satan, who lies to you in order to murder your soul and send you to hell. You would be horrified if you paid a contractor to build your house, and when he laid its foundation, he mixed dirt with the concrete to save money. That would weaken the foundation of your house! That would be dangerous. It would be evil to mix sawdust into your child’s food. We want healthy food, stable materials, pure medicine. How much more should we desire the pure word of God?! 

Before our Gospel lesson begins, Jesus warns us, “Enter by the narrow gate for the gate is wide and the way is easy that leads to destruction, and those who enter by it are many. For the gate is narrow and the way is hard that leads to life, and those who find it are few.” The way to destruction is wide, because it is the way of the lies of Satan. Satan’s lies are more numerous than the sand of the seashore. And you’re sure to find one that will fit your fancy. But the way to life is narrow, because there is only one way. And that is Jesus Christ. He alone is the way, the truth, and the life. No one comes to the Father except through him. So, if you want to be certain that you are on the way to eternal life, you should pay careful attention to the pure doctrine. You don’t want to mix the lies of Satan into the teaching of Jesus. If you discovered a cyanide capsule in your bottle of vitamins, you would certainly take it out. How much more should we remove the false teachings that try to pollute our hearts? Jesus describes the way of false teaching as the way of destruction, that is, the way to hell. He describes false teachers as ravenous wolves dressed like sheep. What do ravenous wolves do when they get into a sheep fold? How do the sheep fare? Are we not sheep? Should we not take heed of this warning from our Good Shepherd?  

People get uncomfortable with this lesson from Jesus, because he warns us against those within the Christian Church, who teach falsely. He’s not warning us here against the militant atheist, who will teach your teenager that we evolved from random chance. He’s not warning us here against the pornographer, who seeks to steel the soul of your children and spouse. He’s not warning against the Muslim cleric or the Buddhist monk. It should be obvious to every Christian that you should avoid these influencers at all costs. He’s here warning against those who bear the name Christian, who may say things you like, who make you feel comfortable.  

Many say, “Why make a big deal about pure doctrine? Isn’t all that matters is that you’re a Christians and believe in Jesus? Won’t people in other Christians churches also go to heaven?” It is most certainly true that all who believe in Jesus with their hearts and confess him as Lord with their mouths will be saved.” (Romans 10:10) And there are many within the Roman Catholic, Eastern Orthodox, Reformed, Baptist, and many other Christian denominations, who trust in the Lord Jesus for forgiveness and salvation and they truly will be saved just as we will be. It is possible to believe some false doctrine and still be saved. But it is also possible to live with only one lung or one kidney. It’s possible to survive with your legs, arms, and eyes amputated. But it certainly isn’t desirable. In fact, it can be quite harmful!  

There are Christian ministers that say that it is okay to believe that the creation account as recorded in Genesis is a myth and that God did not really create Adam out of the dust of the ground. But if you are unwilling to believe that God formed Adam out of the dust of the ground, how can you believe that God will raise your mortal body from the dust of the earth? How can God give new life to all those who have perished and whose bodies have rotted away and turned to dust? How could God have raised Christ? And it is no surprise that those who accept the theory of macro-evolution and who dismiss Genesis as a myth soon dismiss other or all miracles of the Bible and many reject the chief article of the Christian faith.  

Christians are under increased pressure to accept homosexual and transgender ideologies, so many Christian ministers are now saying that homosexuality and transgenderism are not sins. Yet, the acceptance of these ideologies makes it impossible to understand what God intends for how men and women should behave, for marriage, for children, for chastity, for the relationship between Christ and his Church. Indeed, if sociologists spent a thousand lifetimes observing men, women, and children, and the affect marriage has on them, they would still not understand a fraction of what God knew when he created them male and female. And if we cannot fully grasp with our intellect the profound good in the distinction between men and women, and marriage between one man and one woman, we certainly cannot grasp the evil done by destroying these things instituted by God.  

Many Christians reject Baptism. Some Lutherans will dismiss this as just a minor error, but it is very serious. People reject Baptism, because they think that they must choose God instead of God choosing them. And because they refuse to simply take Jesus at his word, they deprive children of the saving washing. Many deny that Jesus can be present bodily in the Lord’s Supper, because a man cannot be present in more than one place at one time. But if Christ cannot be present in the Supper, then he cannot be true God and man. And if he were only present here as God, then he would not be with us as the one who was crucified for our sins, that is, as the one who saved us. So, you see that all of these false teachings lead to even worse errors. Pure doctrine is one united body. No amount of false doctrine is safe.  

It is true that some who believe some false doctrine will nevertheless be saved. Yet, there is false doctrine that makes one not a Christian, and therefore, outside of salvation. Those who deny that Jesus is God and man cannot be saved. Those who deny that God is the Holy Trinity cannot be saved. Those who deny that Jesus died for the sins of the whole world and rose again from the dead, so that whoever believes in him will not perish, but have eternal life, cannot be saved. Those who refuse to repent of their sins, but rather persist in them, cannot be saved.  

The most damaging false teaching, which takes many forms, is that we can be saved by our own good works. But if we can be saved by our own works, by being good people, then we are not saved by the suffering and death of our Lord Jesus Christ. The teaching that good works save replaces Christ Jesus as our true Savior. This false teaching must be rejected at all costs. It blasphemes Christ by saying that his precious blood is not enough to pay for the sins of the world. This is to deny that Jesus is God and Lord. The teaching that good works save robs us of our salvation and confidence. This is why we must avoid all false teaching. All false teaching comes from Satan. So, the goal of all false teaching is to rob you of Christ Jesus as your true treasure.  

Perhaps the most terrifying passage in all of Scripture is where Jesus says that there will be many who will claim to prophesy, exorcise demons, and do mighty works in Jesus’ name, who will cry out to Jesus, “Lord, Lord!”, yet to whom Jesus will say, “I never knew you; depart from me, you workers of lawlessness.” Will Jesus say that to me? I cry out to Jesus today. I call him Lord. Will I call him my Lord on the Last Day only to hear him respond, “I never knew you.”, before casting me into hell? How can I be certain that Jesus will not say those horrid words, but will instead say, “Enter into the joy of your Master.”?   

Only the pure doctrine of Christ can give you that confidence. Jesus says at the end of his Sermon on the Mount that he who hears his words and does them will be like a man who builds his house on the rock, and that house will survive the rain, and the wind, and the floods. Jesus here is saying the same as St. Paul in Romans chapter eight where he says, “For I am sure that neither death nor life, nor angels nor rulers, nor things present nor things to come, nor powers, nor height nor depth, nor anything else in all creation, will be able to separate us from the love of God in Christ Jesus our Lord.”  

Pure doctrine gives you confidence that you have built your faith on solid rock, because it teaches that Jesus Christ has fully paid for your sins by his innocent suffering and death. Pure doctrine teaches that Jesus is true man, so he could take your place. Pure doctrine teaches that Jesus is true God, so that his death on the cross fully pays for the sins of the whole world. Pure doctrine teaches that Jesus is risen from the dead and truly intercedes for you in heaven, even as he showers you with his grace on earth through his holy Word and Sacraments. Pure doctrine assures you that since Jesus has done everything necessary to save you, that only faith can receive this salvation as a gift. Your good works cannot save you, just as your sins cannot damn you. Pure doctrine gives you confidence in your salvation, because pure doctrine comes straight from Jesus.  

But can you truly know pure doctrine? Indeed, you can. God’s word is a lamp to our feet and a light to our path (Psalm 119:105). Learn your Catechism by heart. It clearly articulates the teaching of the Bible. Come to church and listen to the sermon and judge it according to Holy Scripture. Read the Bible. Come to Bible class and ask questions. Read, mark, learn, and inwardly digest the Holy Scriptures. Be a student of the Holy Spirit, a disciple of Christ. Lean not on your own understanding, but believe God’s Word, all of it, even if it seems impossible. This is what it means to have Christ as your true teacher. And if you store up Christ’s words in your heart, you will never be put to shame. Amen.