Transforming the Heart, Taming the Tongue

This is the second sermon in the series "Watch Your Mouth",

Make a tree good and its fruit will be good, or make a tree bad and its fruit will be bad, for a tree is recognized by its fruit. You brood of vipers, how can you who are evil say anything good? For the mouth speaks what the heart is full of. A good man brings good things out of the good stored up in him, and an evil man brings evil things out of the evil stored up in him. But I tell you that everyone will have to give account on the day of judgment for every empty word they have spoken. For by your words you will be acquitted, and by your words you will be condemned. (Matthew 12:33-37 NIV)

We’ve all said things we wish we could take back, but managing our vocabulary with human willpower alone never seems to work. We will be looking at the spiritual anatomy of speech to uncover why our everyday talk is actually a heart issue—because just like a physical doctor checks your tongue to evaluate your bodily health, God uses our speech as a visible diagnostic tool for an invisible heart condition. The truth is, your mouth is simply the loudspeaker for as we dive into Matthew 12 and Luke 6 to discover how real, lasting transformation only happens when we surrender our inner reservoir to the Master Surgeon. 

Scripture 

Luke 6:37-49 NIV [37]  “Do not judge, and you will not be judged. Do not condemn, and you will not be condemned. Forgive, and you will be forgiven. [38] Give, and it will be given to you. A good measure, pressed down, shaken together and running over, will be poured into your lap. For with the measure you use, it will be measured to you.” [39] He also told them this parable: “Can the blind lead the blind? Will they not both fall into a pit? [40] The student is not above the teacher, but everyone who is fully trained will be like their teacher. [41]  “Why do you look at the speck of sawdust in your brother’s eye and pay no attention to the plank in your own eye? [42] How can you say to your brother, ‘Brother, let me take the speck out of your eye,’ when you yourself fail to see the plank in your own eye? You hypocrite, first take the plank out of your eye, and then you will see clearly to remove the speck from your brother’s eye. [43]  “No good tree bears bad fruit, nor does a bad tree bear good fruit. [44] Each tree is recognized by its own fruit. People do not pick figs from thornbushes, or grapes from briers. [45] A good man brings good things out of the good stored up in his heart, and an evil man brings evil things out of the evil stored up in his heart. For the mouth speaks what the heart is full of. [46]  “Why do you call me, ‘Lord, Lord,’ and do not do what I say? [47] As for everyone who comes to me and hears my words and puts them into practice, I will show you what they are like. [48] They are like a man building a house, who dug down deep and laid the foundation on rock. When a flood came, the torrent struck that house but could not shake it, because it was well built. [49] But the one who hears my words and does not put them into practice is like a man who built a house on the ground without a foundation. The moment the torrent struck that house, it collapsed and its destruction was complete.”

Introduction: 

This is week two of our series, "Watch Your Mouth,".

Last week, we looked at the incredible, raw power of the tongue. We discovered that this tiny muscle sits behind our teeth like a stick of spiritual dynamite—capable of clearing the way for Kingdom progress, or blasting our relationships, families, and ministries to pieces. We realized that we have to watch our mouths because our words carry the power of life and death.

But today, we have to move from the symptom to the source.

Whenever you go to the doctor for a physical checkup, they will often ask you to perform a very simple task. They will pull out a tongue depressor, shine a little flashlight, and say, "Open up and say, 'Ah.'"

Now, why do they do that? The doctor isn't actually that interested in your tongue itself. They aren’t checking to see if your tongue is muscular or well-trained. They are looking at your tongue because the state of your tongue is a primary indicator of what is happening inside your body. It reveals signs of dehydration, infection, vitamin deficiencies, or digestive issues. The tongue is an external billboard for internal health.

In the exact same way, God uses our speech as a spiritual stethoscope. Your mouth is the billboard for your soul. If you want to know what the true condition of your spiritual life is, you don’t look at how high you jump on Sunday morning; you look at how you talk to people everyday.

Here’s our text for today’s sermon:

Text: 

Matthew 12:33-37 NIV[33]  “Make a tree good and its fruit will be good, or make a tree bad and its fruit will be bad, for a tree is recognized by its fruit. [34] You brood of vipers, how can you who are evil say anything good? For the mouth speaks what the heart is full of. [35] A good man brings good things out of the good stored up in him, and an evil man brings evil things out of the evil stored up in him. [36] But I tell you that everyone will have to give account on the day of judgment for every empty word they have spoken. [37] For by your words you will be acquitted, and by your words you will be condemned.”

1. The Mouth is Only a Loudspeaker

Notice the direct pipeline Jesus establishes here. He says in verse 34, "For the mouth speaks what the heart is full of."

The New King James translation puts it this way: "Out of the abundance of the heart the mouth speaks."

Imagine you are driving down the freeway, and a song comes on the radio that you absolutely despise. It’s annoying, it’s grating, and it's making you miserable. To fix the problem, do you pull over to the side of the road, grab a screwdriver, rip the dashboard apart, and start smashing the speakers?

Of course not! Why? 

Because you know the speaker didn't write the song. The speaker didn't produce the music. The speaker is just the delivery mechanism. The speaker is simply amplifying whatever station the tuner is dialed into. If you want to change what is coming out of the speaker, you don't fix the speaker—you change the station.

Your mouth is nothing more than a loudspeaker for your heart.

When you lose your temper and say something incredibly cruel to someone you love, and then immediately say, "I'm sorry, I don't know where that came from, that's not really me"—Jesus looks at us gently but directly and says, "Actually, yes it is."

The pressure of the moment didn't invent the anger; it just squeezed the heart until what was already inside leaked out of the mouth. If frustration, bitterness, insecurity, or jealousy are stored up in the reservoir of the heart, then frustration, bitterness, insecurity, and jealousy will inevitably pour out of the spigot of the lips.

Look at 

Luke 6:45 NIV A good man brings good things out of the good stored up in his heart, and an evil man brings evil things out of the evil stored up in his heart. For the mouth speaks what the heart is full of.

This is where so many of us stumble. We treat our speech like an etiquette problem instead of a spiritual problem.

We try to use willpower to "bite our tongue" or white-knuckle our way through a conversation without saying something reckless. 

We try to dress up the outside. But trying to fix your speech without addressing your heart is like taping apples onto a dead oak tree and trying to convince people you have a healthy orchard. The fruit might look attached for a moment, but there is no life flowing to it. It’s an illusion.

We cannot manage the tongue from the outside in. True alignment with God's will is a continuous process of deep self-reflection and inner transformation.

If your mouth struggles with gossip, the solution isn't just a vow of silence; it's asking God to heal the insecurity in your heart that makes you feel bigger by making others look smaller.

If your mouth struggles with constant complaining and cynicism, the solution isn't just forcing a smile; it's asking the Holy Spirit to root out the entitlement and ungratefulness in your heart, replacing it with an active awareness of God’s daily grace.

James 3:7-8 NIV [7] All kinds of animals, birds, reptiles and sea creatures are being tamed and have been tamed by mankind, [8] but no human being can tame the tongue. It is a restless evil, full of deadly poison.

Jesus raises the stakes significantly in verses 36 and 37 of our text He reminds us that our words are being recorded in Heaven's ledger. 

Matthew 12:36-37 NIV . [36] But I tell you that everyone will have to give account on the day of judgment for every empty word they have spoken. [37] For by your words you will be acquitted, and by your words you will be condemned.”

An "empty" word is a careless word. It’s a word spoken without regard for its kingdom impact. It’s the text message sent in a fit of rage, the sarcastic comment meant to sting, the white lie told to protect our pride.

Why is the judgment so severe for mere words? 

Because our words provide the undeniable evidence of who we actually are. They are the fruit that identifies the tree. Your words show whether the Holy Spirit is truly ruling the throne room of your heart, or if your flesh is still running the show.

Conclusion & Invitation: Changing the Reservoir

So, how do we change the station? How do we clean up the fruit? 

We have to change what is being stored in the reservoir.  

Look  at:Psalms 51:10 NIV Create in me a pure heart, O God, and renew a steadfast spirit within me.

David didn't pray, "Lord, fix my bad language." He prayed:

"Create in me a pure heart, O God, and renew a steadfast spirit within me."

Psalms 119:11 NIV says I have hidden your word in my heart that I might not sin against you.

This doesn't mean keeping it a secret. In ancient Hebrew culture, the "heart" wasn't just the seat of emotions; it was the center of your mind, thoughts, and decisions. "Hiding" something there means packing it away for safekeeping, like putting valuables in a vault. 

When you face a tough choice, a temptation, or a moment of crisis, you don't have to scramble to look up a rulebook. The right path is already inside you, ready to guide your reactions in real-time.

Think of it like a trained first responder. They don't read the manual during an emergency; they study it so intensely beforehand that when crisis hits, their training kicks in automatically. That is what internalizing scripture is meant to do for your daily life and faith.

If you fill the reservoir of your heart with the truth of God's Word, with the reality of His goodness, and with intentional gratitude, then when life squeezes you, grace is what will pour out. When a crisis hits you, faith is what will be broadcast through your loudspeaker.

Let’s stop trying to merely patch up our speech with human effort. Let’s invite the Master Physician to do a deep, internal heart work. Let’s slow down, practice regular self-reflection, and open ourselves up entirely to His guidance.

Most Holy God, we come before You today recognizing that our lips have often betrayed the true state of our hearts. Lord, we confess that bitterness, pride, and anxiety have too often found a microphone in our speech. We ask today for an internal transformation. Create in us pure hearts, O Lord. Flood the reservoirs of our souls with Your Holy Spirit and Your truth, so that every word that crosses our lips brings honor to Your name, builds up Your people, and reflects Your sovereign love. In the mighty and matchless name of Jesus we pray, Amen.

The Hidden Explosive: Dynamite in Your Dentures

This is the first sermon in the series titled "Watch Your Mouth,". Over the next few weeks, we are going to look closely at a tiny part of the human anatomy that has the power to alter the course of your entire life.

"The Hidden Explosive: Dynamite in Your Dentures"

When we put bits into the mouths of horses to make them obey us, we can turn the whole animal.  Or take ships as an example. Although they are so large and are driven by strong winds, they are steered by a very small rudder wherever the pilot wants to go. Likewise, the tongue is a small part of the body, but it makes great boasts. Consider what a great forest is set on fire by a small spark. The tongue also is a fire, a world of evil among the parts of the body. It corrupts the whole body, sets the whole course of one’s life on fire, and is itself set on fire by hell. (James 3:3-6 NIV) 

Imagine a construction crew standing before a massive, solid granite cliffside. They need to clear a path for a highway. To do it, they don't use picks and shovels. They drill deep into the rock, pack it with sticks of dynamite, run a wire to a safe distance, and press the plunger. In an instant, what was solid and immovable is shattered into dust.

Dynamite is a fascinating thing. Kept in a secure, temperature-controlled environment, it sits completely still. It looks harmless—almost like a collection of candles. But the moment a spark hits it, its latent, hidden energy is unleashed with terrifying, unstoppable force.

Every single one of us is carrying a spiritual stick of dynamite. You didn’t leave it in your car, or the bedroom, or the kitchen and you didn't pass it through a security detector. It is sitting right behind your teeth. Whether you have your original teeth, a bridge, implants, or no teeth at all, the spiritual reality remains exactly the same. The "dynamite" isn't the porcelain or the enamel; the dynamite is the tongue.

Scripture:

James 3:3-12 NIV [3] When we put bits into the mouths of horses to make them obey us, we can turn the whole animal. [4] Or take ships as an example. Although they are so large and are driven by strong winds, they are steered by a very small rudder wherever the pilot wants to go. [5] Likewise, the tongue is a small part of the body, but it makes great boasts. Consider what a great forest is set on fire by a small spark. [6] The tongue also is a fire, a world of evil among the parts of the body. It corrupts the whole body, sets the whole course of one’s life on fire, and is itself set on fire by hell. [7] All kinds of animals, birds, reptiles and sea creatures are being tamed and have been tamed by mankind, [8] but no human being can tame the tongue. It is a restless evil, full of deadly poison. [9] With the tongue we praise our Lord and Father, and with it we curse human beings, who have been made in God’s likeness. [10] Out of the same mouth come praise and cursing. My brothers and sisters, this should not be. [11] Can both fresh water and salt water flow from the same spring? [12] My brothers and sisters, can a fig tree bear olives, or a grapevine bear figs? Neither can a salt spring produce fresh water.

Introduction: 

Today, we are launching a new sermon series titled "Watch Your Mouth,". Over the next few weeks, we are going to look closely at a tiny part of the human anatomy that has the power to alter the course of your entire life.

Before we look at the Word together, I want you to imagine a construction crew standing before a massive, solid granite cliffside. They need to clear a path for a highway. To do it, they don't use picks and shovels. They drill deep into the rock, pack it with sticks of dynamite, run a wire to a safe distance, and press the plunger. In an instant, what was solid and immovable is shattered into dust.

Dynamite is a fascinating thing. Kept in a secure, temperature-controlled environment, it sits completely still. It looks harmless—almost like a collection of candles. But the moment a spark hits it, its latent, hidden energy is unleashed with terrifying, unstoppable force.

Every single one of us is carrying a spiritual stick of dynamite. You didn’t leave it in your car, or the bedroom, or the kitchen and you didn't pass it through a security detector. It is sitting right behind your teeth. There is "dynamite in your dentures." 

What about those of you that don’t have dentures? Well; Whether you have your original teeth, a bridge, implants, or no teeth at all, the spiritual reality remains exactly the same. The "dynamite" isn't the porcelain or the enamel; the dynamite is the tongue.

Here’s our text for today;

James 3:3-6 NIV [3] When we put bits into the mouths of horses to make them obey us, we can turn the whole animal. [4] Or take ships as an example. Although they are so large and are driven by strong winds, they are steered by a very small rudder wherever the pilot wants to go. [5] Likewise, the tongue is a small part of the body, but it makes great boasts. Consider what a great forest is set on fire by a small spark. [6] The tongue also is a fire, a world of evil among the parts of the body. It corrupts the whole body, sets the whole course of one’s life on fire, and is itself set on fire by hell.

1. There is Disproportionate Power of the Tongue

Look at the three-part blueprint James uses to expose the hidden power of the tongue. He shows us that disproportionate control belongs to the smallest elements. 

We see it in the bit that subdues a powerful 1,200-pound stallion. We see it in the rudder that commands a giant ship against the fury of ocean gale winds. And we see it in the spark of a single match that unleashes a raging inferno across millions of acres.

In every single case, the message is identical: don't misjudge the size of the instrument, because the scale of its influence is monumental.

What’s the point the Holy Spirit is making through James? The point is that the tongue is a tiny muscle—accounting for a mere fraction of your total body weight—yet it is a major force shaping your life. The words you speak have a massive, disproportionate sway over your daily life.

Look at Proverbs 18:21 NIV The tongue has the power of life and death, and those who love it will eat its fruit.

Notice that it doesn't say the tongue has the power to influence life and death. It says it holds the power of life and death. Your words carry spiritual weight. Every day, you and I are using our speech to either breathe life into our relationships, our careers, and our church, or we are using it to speak of death, decay, and defeat over them.

2. The Danger of Uncontrolled Fire

James warns us that when the tongue is left unchecked, it behaves exactly like a wildfire.

James 3:6 NIV The tongue also is a fire, a world of evil among the parts of the body. It corrupts the whole body, sets the whole course of one’s life on fire, and is itself set on fire by hell.

Think about how a wildfire operates. It starts small. A casual comment. A little bit of juicy gossip passed along under the guise of a "prayer request." A sharp, sarcastic jab at a family member or a close friend over the phone because you've had an exhausting day. It feels completely insignificant at the time and you think nothing of it. But in the spiritual realm, that spark starts a fire and  fire spreads. That one sharp comment creates a wall of emotional distance. That piece of gossip fractures a friendship. 

We think the comment was forgotten, but it was actually smoldering beneath the surface the entire time. By the time the visible fire finally breaks out and consumes the relationship, it is simply the inevitable result of a foundational collapse that started with the weight of our own words. Before you know it, the relationship is in flames, and you’re standing over the smoldering ruins wondering, "How did it get this bad?"

It got that bad because we underestimated the spark.

James doesn't mince words about where the spark gets its fuel, he says  "it is itself set on fire by hell." 

Let’s read the verse James 3:6 NIV The tongue also is a fire, a world of evil among the parts of the body. It corrupts the whole body, sets the whole course of one’s life on fire, and is itself set on fire by hell.

When we use our mouths to tear down, to lie, to manipulate, to complain, or to sow discord, we are allowing the enemy to use our vocal cords as a microphone for his agenda. We become standard-bearers for the kingdom of darkness using the very mouths that were created to praise the King of Kings.

James 3:9-10 NIV [9] With the tongue we praise our Lord and Father, and with it we curse human beings, who have been made in God’s likeness. [10] Out of the same mouth come praise and cursing. My brothers and sisters, this should not be. 

3. Harnessing the Energy for Kingdom Purpose

Let's go back to the dynamite analogy we started with; Is dynamite inherently evil? No it isn’t.

In the hands of a skilled engineer, dynamite blasts through mountains so that tracks can be laid, roads can be built, and people can be connected. But in the hands of a criminal, dynamite destroys lives and robs banks. The power is the same; the outcome depends entirely on who is controlling the source.

Your tongue has incredible potential energy. Left to its own devices—controlled by the flesh—it will blow up your life. But when it is fully submitted to the authority of Jesus Christ, that exact same power can be used to blast through spiritual barriers.

James 3:7-8 NIV  [7] All kinds of animals, birds, reptiles and sea creatures are being tamed and have been tamed by mankind, [8] but no human being can tame the tongue. It is a restless evil, full of deadly poison.

James uses the vivid imagery of a wildfire to describe the tongue left to its own devices. On its own, controlled by human impulse, the tongue is an unstable force capable of burning down an entire life.

If it is left to us, it blows things up. The only way to harness that incredible potential energy—transforming it from a destructive wildfire into a spiritual breakthrough—is to place it under the absolute authority and taming power of Jesus Christ.

Uncontrolled by the Spirit, the fleshly tongue acts as a destructive catalyst that ravages everything in its path. But when brought under total authority, everything changes.

When the tongue is yielded completely to the Holy Spirit, that exact same intensity that once caused destruction is now channeled into divine purpose.   Guided by the Holy Spirit, this small part of the body safely and powerfully navigates the entire life through the roughest seas of human emotion and conflict, speaking words of life, healing, and truth.

Look at Proverbs 12:18 NIV The words of the reckless pierce like swords, but the tongue of the wise brings healing.

Imagine the shift in our lives if we stopped using our words as swords and started using them as medicine. Imagine the shift in our personal lives if we stopped using our mouths to describe our problems and started using them to declare the promises of God.

When you use your voice to encourage someone who is ready to quit, you are using Kingdom dynamite. When you use your mouth to speak truth in love, to pray fervently for a brother or sister, or to worship God in the middle of a dark storm, you are blasting away the strongholds of the enemy.

Conclusion & Invitation: Submitting the Plunger to the Master

Maintaining a strong spiritual foundation is a continuous process. It is not a quick fix. It requires daily self-reflection and a constant willingness to open ourselves up to God’s guidance. And there is no better place to start that self-reflection than by evaluating the words that cross our lips.

Who is holding the plunger to the dynamite in your mouth today? Is it your emotions? Is it your anger? Is it the cultural climate around you? Or is it the Holy Spirit?

We cannot tame the tongue on our own strength. 

James 3:7-8 NIV [7] All kinds of animals, birds, reptiles and sea creatures are being tamed and have been tamed by mankind, [8] but no human being can tame the tongue. It is a restless evil, full of deadly poison.

No human being can tame it. It requires supernatural intervention. It requires us to bring our mouths to the altar and say, "Lord, edit my thoughts, guard my lips, and let my words align perfectly with Your sovereign will."

Heavenly Father, we acknowledge today the incredible weight and power of the words we speak. Forgive us for the times we have allowed our tongues to scatter sparks of fire into our homes, our workplaces, and our church. Holy Spirit, we invite You to take absolute control of our speech. Set a guard over our mouths. May the words of our mouths and the meditations of our hearts be pleasing in Your sight, O Lord, our Rock and our Redeemer. In Jesus' mighty name, Amen.