The following message was delivered at Grace Community Church in Sun Valley, California, by Phil Johnson, Executive Director of Grace To You. It was transcribed from the audio of the message titled, “Wisdom Guards the Heart” (GCC-JOH-030). A copy of the CD or a tape can be obtained by calling 1-800-55-GRACE.


Wisdom Guards the Heart
Proverbs 4:23

Copyright 2004
Phil Johnson
All rights reserved.

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What I want to do tonight is pretty much take up where we left off this morning, talking about spiritual warfare and the fact that one of the key battlefields in that warfare is the human heart.  I want to look back at the Book of Proverbs, chapter 4—a single verse—Proverbs 4:23.  I want you to turn there, even though it’s only one verse, because we will look a bit at the context.  So, turn there, and while you’re doing that, let me read the verse.  Proverbs 4:23, “Keep thy heart with all diligence, for out of it are the issues of life.”


Now, I want to start by giving you just a very, very short summary of what that proverb means.  What it’s saying is this: your heart is like a reservoir and what comes out of it is what determines the quality and the character of your spiritual life.  If your heart is defiled, it will have consequences in your behavior, your speech, your attitudes, and every area of life.  The heart is the wellspring of life itself, and if you pollute the fountain, you defile all of life.  It’s vital to understand that. 


Now, also, one other thing I don’t want you to miss—and let’s not skip over—is this: that when Scripture speaks of the heart, it’s speaking of your thought life, the core of your soul, where your thoughts and imaginations operate.  We sometimes contrast heart and mind in a way that Scripture really doesn’t.  The heart isn’t set against the mind in Scripture, but normally, when you see Scripture speaking of the heart, it’s speaking of the mind or at least—at the very least—including the mind, because the heart is where Scripture puts the seat of your thought life.  Proverbs 23:7, “As he thinketh in his heart, so is he.”  So, what you think about and how you think, the ideas you entertain in the privacy of your own imagination, that is the true barometer of your spiritual character.


One of the key verses in the New Testament is Mark 7:20-23, where Jesus said this, “That which cometh out of the man, that defileth the man; for from within, out of the heart of men, proceed evil thoughts, adulteries, fornications, murders, thefts, covetousness, wickedness, deceit, lasciviousness, an evil eye, blasphemy, pride, and foolishness.”  Jesus said, “All these things come from within and defile the man.”  He was answering people who had charged His disciples with eating with unwashed hands, and He was saying, you know, “It’s not what goes into you that defiles you, but what comes out of your heart.”  You cannot entertain wicked thoughts without being utterly defiled by them.  In fact, that is, is it not, the very principle our verse is teaching?  “A corrupt tree cannot bring forth good fruit,” Matthew 7:18, “A contaminated well is unhealthy.”  So, it’s vital to guard your heart and keep it from every kind of defilement.


Now, that’s the meaning of our text.  That’s what it’s teaching.  What I want to do in this hour is focus on the practical and doctrinal implications of this command that we’re given in this verse: “Keep your heart with all diligence, for out of it spring the issues of life,” or, as another version has it, “Guard your heart, for it is the wellspring of life.”  There are three clear spiritual and doctrinal ramifications of this verse that I want to highlight for you tonight.  Number one is the duty of guarding the heart; second is the difficulty of guarding the heart; and third is the desirability of guarding the heart.  We’ll look at these one at a time, so, if you’re taking notes, I’ll try to help you get the main points down.


First is the duty of guarding your heart.  The duty of guarding your heart.  This is on the face of it.  Notice, this is an imperative; it’s a command.  There’s a duty that’s clearly set forth in this verse and it’s essential that we embrace this duty and submit to the command.  In fact, I would say that this is the chief practical duty of the Christian life as it pertains to us.  You know, we’re taught by the first question in the Catechism that man’s chief end is to glorify God and to enjoy him forever. And that’s what God made us for—to glorify Him and to enjoy Him—and that’s a fitting statement of our duty with respect to God, but our first and primary duty with respect to ourselves, is the duty stated in this verse: “Keep your heart with all diligence.”  As we’re going to see tonight, that is ultimately the only way you can glorify God and enjoy him forever.


Now, this is not an easy obligation—and we’re going to talk about that when I get to the second point—but the point here is that it, nonetheless, is an important duty.  It’s not easy to keep our thoughts pure and holy, but our sinful thoughts are the first and most important sins we are called to crucify, mortify, put to death.  We saw that a little bit this morning.  Remember, Jesus taught that those sinful thoughts are the source and the fountain of all the evil that defiles us.  That’s interesting, isn’t it?  I mean, Scripture—and Jesus here—is explicitly teaching that you’re not defiled by sin that rubs off on you from the outside.  Think of it.  Jesus, perfectly sinless, came to this earth, dwelt among sinners as a man, and the sin that He lived in the midst of, none of it rubbed off on Him.  Why?  Because there was no sin coming from within to defile him.  The truth is, our own sinful thoughts, what emanates from our own heart, that is the source of every problem we have.  That’s what defiles us. 


When the apostle Paul commands us to mortify the sin that’s in our members, his focus is not on external deeds—I read you that verse this morning, Colossians 3:5—but what he does in Colossians 3:5, when he says, “Mortify the sin that’s in your members,” he gives a long list of the kinds of sin that, basically, come out of the thought life.  Sins that are hatched in an unholy heart; fornication, uncleanness, inordinate affection, covetousness, evil concupiscence—these are all sins that occur in the mind!  They are sins of the passion and of the mind.  So, the process of mortifying sin, as we saw this morning, involves getting control of the mind, the imagination, the passions, the heart.  Paul is calling for internal purification when he says, “Mortify the sin that is in your members.”  He’s not calling merely for the reformation of our external behavior—you understand that, right?  He’s not saying what your mother meant, when you were a child and she said, “Behave!”  She meant, “Act nice.”  Paul means, “Think nice.”  That’s how sanctification works. 


The focus on sanctification, in Scripture, is always about purifying the heart and renewing the mind.  We’re transformed by the renewing of our mind.  The outworking of our sanctification, naturally then, results in a change of behavior.  But a change of behavior, without the renewal of the heart, is not sanctification at all.  In fact, it’s a form of hypocrisy—and I’ll have more to say about that as we go, but first, let me give you some practical steps for guarding your heart.  How can we do this?  What precisely does this verse require of us?  “Keep thy heart with all diligence”—what does that mean?  Scripture gives us some clear guidelines for “keeping our heart” and I want to outline just the basics for you.  So, you ought to write these down.  If you’re taking notes, again, these are sub-points.  I did this this morning, I rarely do this, I hate to confuse you with sub-points, but I’ve got a little list that you need to take down here.


Step one: give your heart to Christ.  You cannot begin to put this principle into practice unless your heart is surrendered to the Lordship of Christ and you are devoted to Him in love.  If you’re not a believer in Christ, that means your heart is not worth keeping!  It’s a heart of stone; it’s cold, it’s dead, it’s spiritually lifeless.  If you’re not a believer, your heart is corrupt and sinful and utterly impotent to produce any kind of righteousness.  You need a wholesale heart renewal, a new heart.  That’s what Jesus meant when He said, “You need to be born again.”  As Scripture describes it—you can study this for yourself, in Ezekiel 36—but as Scripture describes the process of the new birth, regeneration, it’s all about a new heart, the implantation of a new heart.  The Lord says, “A new heart also will I give you, and a new spirit I will put within you.  I’ll take out the stony heart and put in a heart of flesh.”  That is the promise.  That is the biblical description of the new birth.  That is what theologians refer to as regeneration. 


But, it’s all about a supernatural work of God in the heart.  Essentially, a spiritual heart transplant.  It is the wholesale renewal of the heart and the will and the passions.  It’s not something you can do for yourself.  It involves, in effect, spiritual resurrection: life from the dead.  Without it, Scripture says, your heart is utterly incapable of any righteousness whatsoever.  That’s what Romans 8:7-8 means when it says, “The carnal mind is enmity against God, for it is not subject to the law of God, neither indeed can be.  So then, they that are in the flesh cannot please God.” 


There’re no exceptions to that rule, by the way.  What it means is that without regeneration, without a new heart, what you have is a heart that is bereft of any kind of righteousness, incapable of obedience to God, devoid of any true love for Him, unable to do anything whatsoever to please Him.  That’s really what theologians call the doctrine of total depravity.  I didn’t make it up; it’s what the Bible teaches.  If you don’t have a regenerate heart, your heart is not worth keeping, and it’s impossible for such a heart to produce any true righteousness.  But Christ invites us to give Him our hearts. 


Wisdom speaks in Proverbs 23:26 and says this, “My son, give me thine heart.”  That’s the voice of wisdom and I believe that that is also the voice of Christ, who is personified throughout the Book of Proverbs as wisdom.  You can’t truly give your heart to wisdom without devoting your heart to Christ.  According to I Corinthians 1:30, “Christ is made, unto us, wisdom.”  So, if you want to keep your heart, step one is this: give it to Christ.  Devote it to His wisdom.  Devote it to love for Him.  According to Ephesians 3:16-17, the way to be “strengthened by might in the inner man” is to “have Christ dwell in your hearts by faith.”  Give Him your heart.  Embrace Him as the chief object of your love.  Jesus Himself said, “He that loveth father or mother more than Me is not worthy of Me; and he that love his son or daughter more than Me is not worthy of Me.”  If He is not first in your heart, then you have no hope of keeping your heart pure.  It’s as simple as that.


Step two: crucify your mind.  Mortify your evil thoughts.  I already quoted Colossians 3:5, “Mortify, therefore, your members which are upon the earth…fornication, uncleanness, inordinate affection, evil concupiscence, and covetousness, which is idolatry,” but this is a recurring theme in the Apostle Paul’s writings, this idea of putting to death sin in your body, mortifying the sin.  Romans 8:13, “If you live after the flesh, you shall die; but if you, through the Spirit, do mortify the deeds of the body, you shall live.”  What he’s saying is this: put your evil thoughts to death.  Deal with them ruthlessly.  Don’t allow them any breathing room.  Choke the life out of them.  Mortify them.  Romans 13:14, “Put ye on the Lord Jesus Christ and make not provision for the flesh, to fulfill the lusts thereof.” 


By the way, this is one of the marks of the true Christian.  Galatians 5:24 says, “They that are Christ’s have crucified the flesh with the affections and lusts.”  We haven’t done it perfectly.  It’s a process of crucifixion, and that’s a slow death, so those affections and lusts continually come back to plague us; but if you are truly a believer, then at some point and in some way, you have begun the process of crucifying these lusts and affections. 


And Paul says continue the process.  Carry it through to the end, because sinful thoughts are a fierce, deadly enemy that must be met with lethal force, choked out of existence, rooted up, exterminated, and utterly purged from our lives.  That’s the only way to deal with sin in your life—any sin.  Understand what Jesus was saying when He said, “All that defiles you comes from your heart,” He’s saying that every sin that troubles you is hatched in your mind!  If you can control your mind, if you can mortify that sin that’s in your mind, that is the pathway to sanctification.  If you don’t do that, every wicked thought will destroy you, if you don’t destroy it.  And you’ll never get control of your thought life if you’re not proactive, deliberate, ruthless in mortifying and putting to death the sin that’s in your heart.


Step three: put restraints on your heart that will keep you from entertaining iniquity in that private arena of your own mind.  Put restraints on your heart—you can shorten your version to just that—put restraints on your heart.  Get rid of evil influences.  Don’t watch movies or read novels that fill your mind with wickedness.  Have some self-control in what you expose yourself to; in biblical terms, “exercise yourself rather unto godliness.”


Look at the context of our verse now.  Proverbs 4—you should have turned there—Proverbs 4:20—go back to verse 20: “My son, attend to my words; incline thine ear unto my sayings.  Let them not depart from thine eyes, and keep them in the midst of thine heart, for they are life unto those that find them and health unto all their flesh.”  And then our verse, “Keep thy heart with all diligence, for out of it are the issues of life.”  Verse 24, “Put away from thee a froward [or deceitful mouth], and perverse lips put far from thee.  Let thine eyes look right on, and let thine eyelids look straight before thee.  Ponder the path of thy feet, and let all thy ways be established.  Turn not to the right hand or the left; remove thy foot from evil.”  There’s lots of sound advice about how to guard your heart in that passage I just read.  Look at it closely. 


First of all, if you want to guard your heart, you have to guard your ears, verse 20, “Attend to my words; incline thine ear to my sayings.”  Be careful what you fill your ears with.  This verse suggests that the focus of your hearing ought to be the wisdom of God’s Word.  Be attentive.  Incline your ears to these sayings.  I’m amazed at what some Christians fill their ears with.  I could probably tell a lot about the state of your sanctification just by checking the presets on your car radio, right?  I mean, what that tells me is what you listen to when you’re alone and can choose to listen for yourself.  What do you tune into?  What do you tune into?  The shock jocks with their off-color humor and the angry ranting of certain drive time radio personalities?  Do you gravitate to music that’s profane and full of iniquity?  I always wonder why would a Christian ever want to fill his ears with profanity and lewdness, and how can a godly person derive enjoyment from those things? 


Now, I’m not suggesting that all secular music or humor is evil, but I am saying, shouldn’t our listening be dominated by that which edifies?  This passage seems to say so.  Our ears ought to be inclined to the truth of the Word of God.  If that’s not the focus and predominance of what you listen to when you’re alone, with time to think and meditate, then you’re probably not doing a very good job of guarding your heart. 


Next: guard your eyes, verse 21: “Don’t let the truth depart from your eyes” and that’s also echoed in verse 25: “Let thine eyes look right on, and let thine eyelids look straight before thee.”  Keep your eyes where they ought to be or you won’t be able to keep your heart where it ought to be—that’s a simple principle.  Jesus said, in Matthew 6:22-23, “The lamp of the body is the eye.  If, therefore, your eye is good, your whole body will be full of light; but if your eye is evil, your whole body shall be full of darkness.”  That’s a good reason not to watch some of the stuff we watch, isn’t it?  Our culture constantly bombards us with images and entertainment deliberately designed to appeal to the lust of the eyes, and if you don’t know when to turn away and refuse to watch, you aren’t doing a very good job of guarding your heart.


And I’m not speaking only about that which is overtly evil.  That’s a given.  I shouldn’t even have to make that point.  But much of what we watch is simply a waste of time!  That is as detrimental to us, spiritually, as watching evil things, because it fills our hearts with vain thoughts.  The Psalmist wrote in Psalm 119:37, “Turn away mine eyes from looking at worthless things.”  If you sit for hours watching TV—even if you’re only watching the Fox News Channel or Home and Garden Network—you’re probably not doing a very good job of guarding your heart. 


Here’s another one: guard your conscience, verses 21 and 22 say this: “Keep these sayings in the midst of your heart, for they are life unto those that find them and health unto all their flesh.”  When the sage here encourages us to guard our hearts, he is, in effect, urging us to keep a healthy and active conscience.  He’s saying we should cultivate a mind and a conscience that are informed by the Word of God.  In fact, I don’t need to say much about this; it’s self-evident.  Don’t let the voice of God’s wisdom be silenced in your own heart by the hardening of your conscience.


There’s more, verse 24: guard your tongue, “Put away from you a deceitful mouth and put perverse lips far from you.”  Proverbs 17:20 says, “He who has a perverse tongue falls into evil.”  One of the very practical ways you can mortify sin in your heart is by consciously and carefully restraining its expression in your speech.  James 3:2 says, “If any man offend not in word, the same is a perfect man and able also to bridle the whole body.”  If you can control your tongue, you’ll be able to control your mind too.


Here’s another one: guard your feet, verses 26 and 27: “Ponder the path of thy feet and let all thy ways be established.  Turn not to the right hand or to the left; remove thy foot from evil.”  In other words, stay away from places where temptation assaults you.  That’s pretty much just straightforward, simple wisdom.  Jesus taught us to pray, “Lead us not into temptation, but deliver us from evil.”  If you sincerely mean that, then don’t go places where you know you’re going to be tempted.  It’s pointless to pray that prayer if you are willingly going to expose yourself to temptation. 


Now, recently I said some of these things in a message—I think in Grace Life—and someone came to me afterwards and said, “Well, that’s not very balanced.  Why don’t you warn about the dangers of legalism?  You ought to do another message,” he said, “and explain why we shouldn’t be legalistic.”  Well, I have preached on legalism before!  I’ve actually preached on legalism twice from this pulpit and if you want to hear that, you can get the tape.  But, let me just say that I don’t think legalism is the biggest temptation most of us face.  If modern evangelicals have an imbalance, it’s in the other direction, in the direction of worldliness, not legalism.  But, there’s nothing legalistic about what I’m telling you.  I haven’t given you any lists or rules about specific things you can and cannot do.  I haven’t gone beyond what Scripture says.  I’ve only given you a list of principles.  I’m telling you that you ought to avoid temptation.  Again, this is just a basic principle of spiritual and biblical wisdom; it’s not a complex idea. 


Matthew 26:41, “Watch and pray, lest you enter into temptation.  The spirit indeed is willing, but the flesh is weak.” 


I Peter 5:8-9, “Be sober, be vigilant because your adversary, the devil, walks about like a roaring lion, seeking whom he may devour.”  “Resist him,” Peter says, “steadfast in the faith.”


You’re in Proverbs 4…  Look down at verses 14 and 15, “Do not enter the path of the wicked, and do not walk in the way of evil.”  Avoid it.  Do not travel on it.  Turn away from it and pass on.  Don’t “walk in the counsel of the ungodly, or stand in the way of sinners or sit in the seat of the scornful,” and if that sounds legalistic to you, you’re probably having a hard time guarding your heart.


Two more things, and then I’ll move on to the next point.  Keeping your heart also involves a watchful, cautious self-control over your emotions.  Don’t let your emotions drive or control your mind, but vice versa.  Emotions are good, but in their place, just like your arms are good, but they’re not for walking.  Your nose is good, but it’s not very good for driving nails.  In the same way, your emotions are good, but they’re not for thinking.  Scripture condemns the person who thinks with his emotions.  James 3:14-15 refers to that kind of thinking as “sensual wisdom”: wisdom driven by the senses, thinking that is driven by the emotions.  James says this: “This wisdom descendeth not from above”—this sensual wisdom—“but is earthly, sensual, devilish.”  He says it produces “bitter envying and strife in the heart.” 


Listen to Richard Baxter, the great Puritan author.  He said this: “Keep out”—or cast out—“all inordinate passions, for passions violently press the thoughts and forcibly carry them away.  If anger or grief or pleasure be allowed in, they will command your thoughts.”


Another writer says it like this—and I like this—he says, “Emotions are like screaming kids.  Until you calm them down, you can’t be heard.  If you want to get rid of your bad thoughts, control your emotions.”  That’s good advice. 


But, finally and above all, the thing that sums all of this up: control your thoughts.  This is the whole point, and this is the area where the virtue of self-control is most important.  This is the one area where your battle for self-control will be won or lost: your thought life.  If you willingly and deliberately allow yourself to indulge in evil thoughts or wicked fantasies, what this verse says is you’re filling the wellspring of your life with poison—and nothing is more self-destructive!  “Watch over your heart with all diligence, for from it flow the springs of life.”  We’re talking about spiritual warfare this morning.  This is classic warfare issue, right? 


I mean, we’ve got this reservoir up here that feeds water to most of the San Fernando Valley…  And you realize, don’t you, that since the terrorist situation has become such a problem, that thing is guarded carefully, constantly!  Because it’s a great danger if anyone would poison that reservoir.  The Scripture is saying, “Your heart’s like that.  Keep it pure.  Out of it flow the springs of life.”


Now, let’s move on.  That’s the first implication of our text: the duty of guarding the heart.  So, doctrine number one that we want to draw from this text is this: it is your bound and duty to keep your heart.  You need to do it carefully and diligently and conscientiously, and that’s a good place to make the transition to doctrine number two. 


Doctrine number two is the difficulty of guarding the heart.  Our text implies that keeping the heart is not an easy task.  This is not something that comes naturally.  “Keep thy heart,” he says, “with all diligence.”  This is not something that comes easy for anybody.  It requires diligence.  It’s not something that you can do passively.  It calls for effort, perseverance, persistence, constancy, and industry—diligence.  It’s a struggle.  And that’s all an understatement, really. 


Jeremiah 17:9 says, “The heart is deceitful above all things, and desperately wicked; who can know it?” 


Genesis 8:21, God himself says, “The imagination of man’s heart is evil from his youth.”


According to Psalm 51:5, we are “shapen in iniquity.”


Solomon said, in Ecclesiastes 9:3, “The heart of the sons of men is full of evil, and madness is in their heart while they live.”


We are all hopelessly, desperately, and completely wicked in and of ourselves.  That is the state of every fallen human heart.  Again, that’s the doctrine of total depravity.  Romans 3:10, “As it is written: ‘There is none righteous; no, not one.”  Nobody escapes this verdict. 


Now, remember that all the sin we struggle with emanates from our own hearts.  Matthew 15:19-20 (this is a cross-reference to the one I read earlier), Jesus says, “For out the heart proceed evil thoughts, murders, adulteries, fornications, thefts, false witness, blasphemies…These are the things which defile a man.”  So, the heart is the source of our problem in the first place.  We have to guard our heart, not only from evil outside influences, but, more importantly, from the evil that breeds right there within.


Proverbs 28:26, “He that trusts his own heart is a fool.”  Here’s a good lesson: you can never trust your own heart too little, and you can never trust God too much.  We face perpetual threats to the purity of our hearts.  We’ve already mentioned some.  Vain thoughts, mindless, trivial matters that we give our attention to, the pleasures of sin entice us, the lure of the world, the wiles of the devil, the sinful tendencies of our own flesh—all of those things appeal to the wickedness and corruption that lies in our hearts, and that wickedness that’s inside of us is ready to respond to any kind of catalyst.  And you cannot cleanse your own heart.  This is not a problem we can fix for ourselves. 


Proverbs 20:9, “Who can say, ‘I have made my heart clean; I am pure from my sin’?”  The implied answer is nobody can say that. 


Job 14:4, “Who can bring a clean thing out of an unclean one?”  No one! 


I John 1:8, “If we say that we have no sin, we deceive ourselves, and the truth is not in us.” 


So, this is a huge problem.  Our hearts are desperately wicked—and we can’t change that, Scripture says, any more than the leopard can change his spots.  It’s part of our nature.  We can pretend that we’re basically good—that’s what a lot of people do—but that doesn’t change reality.  The great Scottish Puritan, Andrew Grey, said this—and I love this statement—he said, “We conceive that if there were a window opened in each of our bosoms, through which each one of us that are here might behold one another’s hearts, we would become monsters and wonders to one another, and to ourselves likewise, and we might cry out, “Oh, where is the God of judgment that takes no vengeance on such deceitful hearts?”  If our hearts, he says, were turned inside out, so to speak, and we saw the insides of our hearts, we would wonder at God’s patience.  That’s true.  I know that’s true because I’ve peeked in my own heart.  Our hearts are breeding grounds for all kinds of evil.  According to I John 1:10, if you think you’re an exception to this rule, you are self-deceived.  You’re calling God a liar, and His Word is not in you. 


To quote Proverbs 28:26 one more time, “He who trusts in his own heart is a fool.”  That’s why it is no simple task to keep your heart pure.  Remember that Adam had a heart that wasn’t even already defiled by sin, and he kept it pure only a very short time.  The fall occurred before he and Eve had ever conceived a child.  It must have been very soon after their creation.  That shows the difficulty of keeping a pure heart.  That also gives us some perspective on what kind of diligence is required for the keeping of our hearts.  This is something we have to do constantly.  If you keep your heart only part-time pure, that’s nothing but hypocrisy.  It’s an abomination to God.  If the only time you think about these things or the only time you ever strive to obey, even, is when you’re listening to a message on the subject or when you come to the Lord’s Table or when it’s otherwise convenient to examine yourself, then all you’re doing is practicing the religion of the Pharisees.  You’re merely honing the skill of hypocrisy. 


Face it, there are times when it’s fairly easy to guard our hearts.  When we’re under affliction, when we’re under conviction, when we’re in church, or when we’re in public it’s much easier to keep our hearts pure and focused than when we’re alone, in private, or enjoying our leisure.  And, frankly, that’s why trials—that’s one major reason—why trials and difficulties are good for us.  That’s why, when God providentially sends us trials and afflictions, it’s sometimes an act of mercy on His part, because when circumstances force us to be dependent on the Lord, our hearts stay fixed on Him.  But the real test of obedience in this matter is whether you keep your heart pure in private, when you’re alone, when things are going well, when you have opportunities to rest from all the cares of life—your leisure time.  That’s when it’s most vital to keep careful watch over your heart!  Sadly, that is precisely where most of us fail so miserably. 


What’s the solution?  Well, you could devote yourself especially, in your leisure time, to the task of cultivating humility, repentance, holiness, and the fear of God.  Give your private life to God.  It’s relatively easy to be a Christian in public.  It’s fairly simple to search your heart and examine your life if you do it only once a week or if you limit your self examination to those times when you come before the Lord’s Table, but if you do that, God despises your worship. 


Listen to Isaiah 66:2-4.  The Lord says this, “To this man will I look, even to him that is poor and of a contrite spirit, and trembleth at my Word.”  And then it says this: “He that killeth an ox”—and it’s talking here about sacrifices for sin—“is as if he slew a man and he that sacrifices a lamb is as if he cut off a dog’s neck; he that offers an oblation as if he offered swine’s blood; he that burned incense as if he blessed an idol.  Yea, they have chosen their own ways and their soul delighted in their abominations.”  And the Lord says this: “I will also chose their delusions and bring their fears upon them because when I called, none did answer; when I spoke, they did not hear, but they did evil before mine eyes and chose that in which I delighted not.”


In other words, God’s saying, if you choose your own way, if your private life is devoted purely to personal pleasure, where you seek delight in what God deems abominable, then when you come to worship, your worship is unacceptable.  It’s repulsive to God.  Your sacrifice, He says, is no more valid than if you’d offered pig’s blood!  Graphic language, isn’t it?  But what its saying is that your supposed service to God—if you’re a hypocrite—your service to Him offends Him.  You may think you’re sacrificing a lamb, but it’s no more acceptable to God than if you cut off a dog’s neck and offered that to him.  It’s a repulsive picture, isn’t it?  It’s summed up for us in Proverbs 15:8, which says, “The sacrifice of the wicked is an abomination to the Lord.”


So, what’s acceptable to God?  Well, I just read it.  Isaiah 66:2, “Him that is of a poor and contrite spirit, and trembles at my Word.” 


Psalm 51:17 says the same thing, “The sacrifices of God are a broken spirit; a broken and contrite heart, O God, Thou wilt not despise.”  Notice, it’s the offering of our hearts that is acceptable to God!  And, by definition, you cannot do that on a part-time basis.  If God is to have our hearts, He must have the whole heart.  That’s a difficult duty, but think about it.  That is the substance of the first and great commandment, Matthew 22:37, “Thou shalt love the Lord thy God with all thy heart and all thy soul and all thy mind.” 


So, we’ve seen the duty of guarding our hearts and the difficulty of guarding our hearts; here, quickly, is a third doctrine we can glean from this text: the desirability of guarding the heart.  Look at the text again.  “Watch over your heart with all diligence, for from it flow the springs of life.”  It’s sheer folly not to guard your heart, because it’s spiritual suicide!  It’s unbelievably self-destructive.  It’s a sure way to ruin your life.  Poison the wellspring with evil?  Don’t ever trivialize the sins you commit in the privacy of your own heart.  Don’t think for a moment that you can entertain sin in your mind without any danger to your soul, because the sin you cultivate in your imagination directly assaults your soul.  It assaults your conscience.  It poisons your mind.  When you engage in evil thoughts, you are pouring poison directly into the well that supplies all of your life—and you will reap what you sow. 


Cultivating sinful desires removes every barrier from the will that might otherwise keep you from doing the deed.  If you imagine it, you will do it.  The thought is the parent of the deed.  If you foster a desire for sin, you will succumb when temptation presents itself; you won’t have any defense against it.  Micah 2:1 says, “Woe to them that devise iniquity and work evil upon their beds.”  He’s talking about people who lie in bed at night and imagine the evil things they might do, or derive enjoyment from fantasies about evil.  And he says this: “When the morning is light, they practice it because it is in the power of their hand.”  In other words, when the opportunity comes in real life, in the light of day—if opportunity presents itself and you’ve imagined it and enjoyed and thought pleasantly of that evil imagination, you will do it…when the opportunity comes by. 


Hosea says the same thing, but listen to the vivid imagery he uses.  Hosea 7:6-7, “For they have made ready their heart like an oven, whiles they lie in wait: their baker sleepeth all the night; in the morning it burneth as a flaming fire.  They are all hot as an oven, and have devoured their judges; all their kings are fallen: there is none among them that calleth unto Me.”  He’s comparing the mind to an oven where you bake the deeds that come out in your life, and he says, to stoke that oven with evil thoughts is to fan those flames and it will be destructive.  To stoke the mind with evil thoughts is to fan the flames of evil and, if you do that, you won’t have any will to resist when temptation comes. 


Proverbs 25:28 says, “He that hath no rule over his own spirit is like a city that is broken down and without walls.”  So, guard your heart!  It’s the wellspring of your life.  If you defile the fountain, you destroy yourself. 


Galatians 6:7, “God is not mocked.  For whatever a man sows, that also shall he reap.”  That, in and of itself, is a good reason why we ought to guard our hearts.  It’s the only way to safeguard our own well-being. 


But there’s something even more serious at stake here than your earthly reputation and happiness.  When you give your heart to evil thoughts, by entertaining evil in your hearts you incur the wrath of God.  Psalm 66:18 says, “If I regard iniquity in my heart, the Lord will not hear me.” 


Job said something similar.  He knew something about keeping his heart pure, didn’t he?  And he also experienced God’s grace in the midst of his trials.  But he said this: “What is the hope of the hypocrite, though he hath gained?  When God takes away his soul, will God hear his cry when trouble comes upon him?”  Did you realize that it’s the heart and not merely the behavior that God sees and judges? 


In I Chronicles 29:17, David prays this: “I know also, my God, that thou triest the heart, and hast pleasure in uprightness.” 


Jeremiah 17:10, God Himself says this: “I, the Lord, search the heart”—I test the mind!—“even to give to every man according to his ways, according to the fruit of his doings.”


Do you understand that?  God is saying…not that He looks at what we do and then judges us accordingly, but that He looks at our hearts and judges us according to that.  Revelation 2:23 is an echo of that: “I am He who searches the minds and the hearts and I will give to each one of you according to your works.”  God sees every thought of your heart, and He knows your heart perfectly.


Psalm 44:20-21, “If we had forgotten the name of our God, or stretched out own hands to a foreign god, would not God search this out?  For He knows the secrets of the heart.”


Jeremiah 20:12 says, “God sees the mind and the heart.” 


I Chronicles 28:9 says, “The Lord searches all hearts and understands all the imaginations of all of our thoughts.”


In Solomon’s Prayer of Dedication for the Temple, he said this (I Kings 8:39): “Thou even, Thou only knowest the hearts of all the children of men.”


Hebrews 4:13 says, “Neither is there any creature that is not manifest in His sight, but all things are naked and open unto God’s eyes.”


Scripture is full of this truth.  God sees our hearts.  If you would blush to have the secret thoughts of your heart made manifest for everyone in this room to see, you ought to tremble at the reality that God already sees those thoughts and knows them altogether.  Jesus said, “Blessed are the pure in heart, for they shall see God.”  Hebrews 12:14 adds this: “Without holiness, no man shall see the Lord.”  So, this is a vitally important matter.  It underscores the desirability of guarding our hearts.  An impure heart can ruin us for life and all eternity.  There’s no advantage, frankly, to poisoning the wellspring of your heart. 


So, where do we go for a pure heart?  I’ve already spoken of the utter impossibility of cleansing your own heart.  What do we do with defiled hearts?  Well, first and most obviously, we have to repent of the impurity.  David wrote, in Psalm 51:17, “The sacrifices of God are a broken spirit; a broken and contrite heart, Thou wilt not despise.”  He’s talking there about repentance. 


Second, while we can’t cleanse our own hearts, God Himself can cleanse us.  That’s why David prayed also in Psalm 51:19, “Create in me a clean heart, O God, and renew a right spirit within me.” 


Again, if you’re an unbeliever—if you have never trusted Christ for salvation—what you need is a new heart.  I’ve already quoted Ezekiel 36:25-26, where God describes the work of regeneration.  Actually, I referred to it and quoted a snippet of it.  Let me quote it again.  God says this: “I will sprinkle clean water upon you and you shall be clean; from all your filthiness and from all your idols, I will cleanse you.  A new heart also I will give you, and a new spirit I will put within you.  I will take away the stony heart out of your flesh, and I will give you a heart of flesh.”  Acts 15:9 says, “God purifies our hearts by faith.”  Malachi 3:2 says this about Christ: “He’s like a refiner’s fire and like a fuller’s soap.”  He can do that work of cleansing that we so desperately need and cannot do for ourselves. 


If you’re a Christian, part of the work of your sanctification is to go to Him regularly for that kind of forgiveness and cleansing.  If we “confess our sins, He is faithful and just to forgive us our sins, and to cleanse us from all unrighteousness.”  God promises forgiveness from our sins and He imparts to us his own Spirit.  That is what enables us to know His mind, to equip us to think righteous thoughts, to empower us to obey his commandments.  And although we still don’t do that perfectly—because of the weakness of our flesh and the imperfections of our fallenness—Christ, Scripture says, clothes us in the garments of his perfect righteousness so that we can stand before God without fear of condemnation.  That’s the gospel message, and that is the greatest incentive I know for filling our hearts and minds with thoughts of Christ and His glory.


Let’s close in prayer.


Lord, our hearts are humbled by the duty that is set forth before us in this verse. Guard our hearts with all diligence.  We confess that we have not done that as we should; we don’t do that as we should.  Lord, we seek Your cleansing and thank You for the promise of that cleansing, and we pray with David, the psalmist, that You would create in us and constantly recreate in us pure and clean hearts for the glory of Christ in whose name we pray. Amen.


Added to Bible Bulletin Board's "Sermons and Articles Collection" by:

Tony Capoccia
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