Rewire Your Heart: 10 Days To Fight Sin

Scripture: 2 Corinthians 6:11-13

Your Affections Are Restricted

What causes us to sin? What moves us to holiness? What part of us initiates belief? What is it inside of us that generates doubt? There is only one thing – our hearts. 

So what is the main problem in our fight against sin and our lacking in faith? Paul says it like this in our passage for today: 

“You are restricted in your own affections.”

In this short, seemingly off the cuff comment, Paul cuts to the heart of everything – the heart. 

In this chapter, Paul is pleading with the Corinthians to believe the Gospel. He has done everything in his power to share the good news of Jesus with them, but there are people still dragging their feet. Why? 

Their affections are restricting them. 

How can our affections restrict us? It’s simple really. We don’t do anything we don’t want to do. We only ever do what we want. 

Now, that doesn’t mean we only do things we like or prefer. It means that our actions always follow the prevailing desire of our heart. That is why, throughout the Bible, God is chiefly after our hearts.

Our affections restrict us all the time. Our hearts are not all-in. That is why we sin. That is why we doubt. That is why we struggle with our faith and walk. 

So how can we change? How can we beat sin and live for God? We must take the restrictions off our affections. 

The only way to do this is with the Gospel. Only the Gospel is beautiful enough to change our hearts and produce in it all the affections that will cause us to live new lives.

Reflect on all God has done for you in Christ. Rejoice in the fact that your sins are forgiven by the precious blood of the Son of God. Revel in the truth that you have been adopted into God’s family at the high price of the cross. 

When we do this, new affections will spring to life in our hearts. We don’t fight sin by stifling our desires and feelings. We fight sin by taking the restrictions off our affections. We need to feel more, not less. And these feelings need to come from the Gospel.

Throughout this study, we will see how everything comes down to the heart. For more information I invite you to get my full book on this topic: Rewire Your Heart. 

Scriptures: Colossians 2:20-23, Colossians 3:5, Colossians 3:1-2

The Wrong Way To Fight Sin

When you want to stop doing a sin, what do you do? 

Do you try to deprive yourself of something, keep away from tempting situations, or try to distract yourself with more innocuous activities? 

You have probably already learned this through practice, but none of these techniques will ever work. You cannot deprive yourself, ignore your desires, or beat your will into submission. Why? Because your mind and will aren’t the center of your decision-making process. Your heart is. If you don’t love something you won’t do it. If you don’t hate something you won’t leave it alone. 

Yet in so many of the self-help books and even sermons today, people are preaching this strategy. There is always some new “wisdom” for how to stop bad habits and start good ones. Many of them treat sin like a diet. Starve out the bad. Feed the good. But sin doesn’t work like this. 

In our passage for today, Paul is going up against similar religious tactics of his time. He is trying to help his audience fight the indulgences of sinful flesh (Col. 2:23) and what is earthly (3:5). But before he tells them how to do it, he tells them how not to do it. 

People in Paul’s day were saying that the right way to weed out sin was deprivation. “Do not handle, do not taste, do not touch” (2:21). They formed a man-made religion around depriving themselves of basic goods – “asceticism” (2:23) – and inflicting themselves with wounds – “severity to the body” (2:23). The way to fight sin was to beat it out of yourself and punish yourself when you don’t. 

This is an extreme version of what we do. For instance, if someone struggles with pornography, they might deprive themselves of the internet and technology. And when they fall into it, they inflict themselves with guilt and shame. The problem is deprivation cannot change the heart any more than starving yourself can get rid of hunger.

Maybe this sounds wrong to you. Maybe this is how you thought you were supposed to fight sin. It’s no wonder that Paul said, “These have indeed an appearance of wisdom” (2:23). However, it will never work. Such sin tactics “are of no value in stopping the indulgence of the flesh” (2:23). 

So if that’s how not to fight sin, how should we fight sin? 

Paul has our answer. “Seek the things that are above, where Christ is, seated at the right hand of God. Set your minds on things that are above” (3:1-2). 

How do we fight sin? We set our minds on Christ. You can’t change your heart by saying no to your desires. But you can change your heart by setting your mind on Christ. 

When you remind yourself that you “have been raised with Christ” (3:1), your heart is filled with great affections. These affections will rewire your heart to do what deprivation never could. Setting your mind on Christ and his Gospel will kill sin in your life.

Scripture: Luke 6:43-45

Good or Bad Comes From The Heart

What causes us to do good or evil? Most people seem to think that it comes down to the decisions we make. If you set your mind on doing good you will. If you choose to do evil, you’ll do that instead. 

But Jesus teaches us that the real source of our actions lies much deeper. It all comes down to the heart. 

“The good person out of the good treasure of his heart produces good, and the evil person out of his evil treasure produces evil, for out of the abundance of the heart his mouth speaks” (Lk. 6:45). 

Whatever is in your heart ends up in your life. 

What you treasure, value, glory in, and enjoy will result in what you do. If you treasure good things in your heart, then you will do good. If you treasure evil in your heart, then you will do evil. 

So how do we change what our hearts treasure? The answer, in Jesus’ words, is different than we might expect. We might expect a list of disciplines, habits, or meditations that would change what our hearts value. 

However, the condition of your heart is not based on what you do, but who you are. Jesus taught that a good tree can’t bear bad fruit and a bad tree can’t bear good fruit. Only good trees can bear good fruit. 

So we must ask, how do we become a good tree? 

That is the work of the Gospel. Jesus makes us a good tree despite all our bad fruit. He saves us and transforms us before we have done anything to earn that transformation. 

All we need to do is see ourselves as the good tree Jesus has made us to be, and our hearts will treasure him above all else. 

Do you want to change your actions? Treasure Jesus for making you into a good tree even when you were the worst tree there was. He will then work in your heart to bear good fruit.

Scriptures: James 1:14-15, James 4:8

Sin Doesn’t Come From Temptation

I grew up thinking temptation was where sin came from. On any given day, I would be going about my business and then temptation would spring to life: a pretty girl would walk by, a friend would launch into a dirty joke, a copy of next week’s test would fall into my hands. It was my duty, then and there, to fight temptation by saying no to it or fleeing from it altogether. Temptation was the enemy. Defeat meant sin.

But the problem is not temptation. The real problem is in the heart where our desires lie. 

Temptation cannot exist where desire does not first exist. You cannot be tempted to do something you do not first want.

The Bible teaches that desire brings about temptation. “Each person is tempted when he is lured and enticed by his own desire. Then desire when it has conceived gives birth to sin, and sin, when it is fully grown, brings forth death” (1:14–15). When does temptation occur? After the desires have enticed us. Temptations do not produce desires, but desires produce temptations.

Temptation cannot exist where desires do not exist. I cannot tempt you to eat concrete, if there is not already something desirous of consuming concrete within you. Since you know that eating concrete would be not only unpleasant but harmful to your body, the temptation would never succeed. In fact, calling it a temptation at all is a misnomer. You cannot call something a temptation that is not tempting in the slightest. For temptation to exist, desire must first exist.

All temptation can do is point out the opportunity to fulfill existing desires. Think about the familiar taunt offered by tempters, “You know you want it.” Temptation holds up the object of our desire and seeks to make it even more desirable.

Only when we focus on our internal desires instead of our external temptations will we be addressing sin at a deeper level. Only when we look at what we want, not just what we do, will we be getting nearer to where the battle for sin is truly taking place. 

And how does change take place at this deeper level? How are the desires of our heart transformed? As we have seen throughout this study, the only way the heart can be changed is by the Gospel. Enjoy Jesus, and he will change your heart. 

Only God can bring this change. So may we follow James’ words from later in his letter, “Draw near to God, and he will draw near to you” (4:8). 

Scripture: Matthew 6:25-30

Belief Changes Hearts 

What lies at the bottom of our sins? Throughout this study, we have seen that the heart plays a central role in leading us into sin or holiness. But what affects the heart? 

Jesus showed us in the Sermon on the Mount that unbelief lies at the bottom of all our sins. 

Jesus commanded his followers not to be anxious about what they would eat, drink, or wear. How is that possible? To this day people have to toil and scrape to get by, living paycheck to paycheck. How will I feed my family, pay my mortgage, fix the car? Jesus’ answer is to have faith in God’s provision (Matt. 6:25–30). What we believe changes our hearts. 

Jesus teaches us an important truth about how our hearts work. In a sense he says, “Since God does the little stuff, surely he’ll do the big stuff too.” God feeds birds and clothes grass. That is evidence that he will feed you and clothe your children. Believe that God is a provider and anxiety will be removed from your heart. What you believe changes your heart. 

However, unbelief says the opposite to our hearts. As Jesus pointed out, the sin of worry reveals the underlying disbelief in God’s provision. We worry because we do not believe God will provide. Disbelief of all kinds regularly fills our hearts and produces its corresponding and inevitable sin. 

God’s power is not able to provide. God’s love is not enough to satisfy. God’s law is not aligned with my joy. Jesus’ blood is not sufficient for my sin. The Holy Spirit’s operation is not adequate for my sanctification. The Gospel can’t heal my marriage, pull me from my addiction, or silence the bitterness in my heart. We doubt that God is enough.

If we can’t trust God, who can we trust? By our actions all of us have answered this question with a resounding, “Myself!” I will meet my needs. I will fulfill my desires. When we try to fulfill our wants by our own devices, the only solution we will ever contrive is sin. When our hearts are filled with unbelief, everything our hands lay hold of will be fashioned into idols of our own making for our own satisfaction. O we of little faith!

So how can you fight sin? Change your heart. How can you change your heart? Change your beliefs. 

Believe that Jesus has provided everything you need in the Gospel and your heart will begin to run from sin and toward God. 

Scripture: Isaiah 29:11-14

God Wants Your Heart

What is God after? What does he want from us? Is he after a song on Sunday or a really good prayer at night? I think we all know the answer is no. God is after our hearts. 

One of the clearest moments in the Bible where we learn this truth is in Isaiah. God is describing through his prophet a siege that is coming upon Jerusalem. 

However, no matter how much the people hear of Isaiah’s words and God’s revelation, they will not really listen. They will be like a person who is given a book but cannot open it and like one who is given a book but cannot read (29:11-12). 

So why this coming punishment? And why can’t the people understand the visions and warnings from God? 

Here is where we get our clear picture of what God is after. Here is the reason. 

“Because this people draw near with their mouth and honor me with their lips, while their hearts are far from me” (29:13). 

God is punishing and blinding his people because they are putting on a show of religion, but their hearts are not in it. They come to God and give him praise and say all the right words, but God does not have their innermost selves – their hearts. 

God wants your heart, not your lips. He wants your affections, passions, desires, and longings. God wants your wants. And he will not be satisfied until he has them. 

Why? Because he knows that only when you desire him will you be desiring something good. And not only will you be desiring something good, in fact the only good, but also the best good. God wants your wants because he wants your good. 

And how will he get your heart? Well, how did he plan to get the hearts of his wayward people in Isaiah’s day? 

He will do wonderful things (29:14). But these wonderful things aren’t pretty. These are things that bring wonder. Things like punishment and mighty acts of judgement. The reason why people were drawing near to God with their lips but not their hearts was because their fear of God was fake. It was a “commandment taught by men” (29:13). 

So God would instill true fear in their hearts. This may sound harsh, but God wanted their hearts. So he would reveal himself to them in the only way that would change them. 

God changes hearts the same way today. He shows himself to us in wonderful ways. And the most wonderful way he has revealed himself to us is also in judgement and punishment. But this time, the judgement and punishment did not come upon us who deserved it. God’s wrath came upon Jesus, who bore our punishment even though he did not deserve it. 

Is your heart far from God even though your lips are close to him? Do you want to change that? Behold Jesus! See how God has revealed himself to you in Christ! Let the fear and love of God pierce your heart by peering deeply into the truth of the Gospel.

Scripture: Psalms 37:4

Fighting Sin With Delight

When times get really hard it becomes so much easier to sin. Psalm 37 is all about how to persevere during a really hard time. 

The Psalmist, David, writes that wicked people are doing terrible things. How should David and the people respond? David says we should respond with stillness, patience, and faith.

But how is that even possible? How can we just sit there and take it? How can we be still when everything is swirling around us? How can we be patient when everything is going wrong? How can we have faith when all hope seems to be lost? 

There is a lot of good advice in this Psalm to answer these questions. But one of the most beautiful, helpful, and famous is found in Psalm 37:4. 

“Delight yourself in the LORD, and he will give you the desires of your heart.” 

This verse is so helpful for two main reasons. 

First, perseverance and fighting sin don’t have to be a sad affair. We are called to find delight! But where are we to find this delight in such bleak circumstances? We can’t find them in our surroundings. We can’t find them just by looking on the bright side. No. 

We find delight in the LORD. We delight ourselves in God. For us as Christians, the best way to do this is by repeating the good news of the Gospel to yourself. Jesus has saved you from sin and death. He has taken your punishment. You have been reconciled to the Father. You’ve been made a temple of the living God. Delight yourself in all God has done for you. 

The second reason this verse is so helpful is because we get something. Not only do we not have to be sad, but we also get to receive something good. We get the desires of our hearts. 

What are these desires in our hearts that we will be given in times of trouble? Well, it is the very thing we have been delighting in. We will get God!

No matter the circumstance and no matter the sin, if you delight yourself in the God of the Gospel you will get the God of the Gospel. Revel in Jesus and Jesus will reveal himself to you.

That is how you fight sin in difficult times. Engage your heart in the fight. Delight yourself in God.

Scripture: Jeremiah 31:31-34

Old Testament Versus New Testament

What’s the difference between the Old Testament and the New Testament? 

The first thing to point out is that the word “testament” means “covenant.” So the real question is, what’s the difference between the old covenant and the new covenant? 

The truth is that there are several differences. But the major difference, brought up by Jeremiah 31:31-34, is the heart. 

The old covenant is the one given to Moses and the people of Israel after their exodus out of Egypt. This covenant came with a law. This law included the famous ten commandments. If Israel kept the law they would be allowed to dwell in God’s presence in relationship with him. 

However, Israel never kept the covenant. They constantly broke God’s law. 

Why couldn’t they keep the covenant? Because the law was outside them. It was not inside them. 

The new covenant would be different. God would write the law of this covenant on his people’s hearts. It would be inside them. 

Laws on the outside can’t change the inside. There must be a change on the inside to obey the law on the outside. 

We try to change ourselves with outside influences all the time. Through all kinds of rules, disciplines, routines, and restrictions, we try to change our actions. We try to fight sin, become holy, and transform our behavior by laws exterior to ourselves. But this will never work. 

Laws can’t change hearts. 

So how does God use the new covenant to change our hearts? He fulfills all the requirements of the covenant for us in Jesus. Jesus died under the curse of the law that we earned and gave us the blessings of the covenant that he earned. He did this at the cost of his life on the cross. Such a sacrifice moves our hearts in a new way. 

But it is not just by hearing this story of the Gospel that our hearts are changed. Something else has to happen. After all, the Israelites were saved from Egypt and their hearts remained hard toward God.  

Something had to happen within us. That is why God gives us the Holy Spirit. The Spirit changes our hearts to actually believe the gospel, enjoy the gospel, and respond to God because of the Gospel. 

The difference between the Old Testament and the New Testament is that the new covenant changes our hearts, so that we can finally obey God freely.

Scripture: Proverbs 4:23

Everything Comes From the Heart

Everything we do comes from our hearts. 

One of the most succinct ways the Bible states this truth is found in Proverbs 4:23. The idea can be stated so succinctly because it contains two metaphors. The first metaphor is pretty familiar to us – your heart. 

In the mind of the author of Proverbs and his original hearers, the heart is the center of a person. The heart is comprised of the thoughts, volition, conscience and more. 

The second metaphor isn’t terribly difficult to understand either. It combines two words in the original language of Hebrew. The first word communicates the idea of the place things begin:  their source, starting point, or the place from where things outpour. The second word communicates life. So the metaphor is like a river of life or the place from where all life flows. 

Combine the two images and you get a picture of all life flowing out of the starting place of the heart. 

According to this verse, our loves and hates, inclinations and feelings, our desires and emotions motivate everything we do. 

Based on this fact, the author of Proverbs implores us to guard our hearts. How do we do that? In the context of this book, the answer is simple: seek wisdom. 

The book of Proverbs is full of things to stay away from and things to pursue. But above all, we need to note, that “wisdom” in Proverbs is a character. She is a person who we seek after and who comes to us. 

Bible scholars have long noted that Jesus is the final embodiment of lady wisdom. He is the one who reveals God to us. He is the one who changes our hearts with his Spirit. He is the Word of God who comes to us. He is the face of God we seek. 

How do we guard our hearts? We seek after Jesus. We rejoice in the truth of the Gospel. We meditate on the gift of the cross. We rejoice in the power of the resurrection. We listen to the teachings of his lips. We follow the voice of his Spirit. We wait eagerly for the return of his full and final presence. 

Everything you do comes from the heart. You want to change what you do? Seek after Jesus and he will guard your heart.

Scriptures: Deuteronomy 29:4, Deuteronomy 30:6

Our Hearts Need God

This is the tenth and final day of our study of the “heart.” After everything we’ve looked at, there is one final question we need to ask. Can we change our own hearts? 

Are we capable of doing the inner work of heart transformation necessary to follow God, adore Jesus, and listen to the Spirit? The answer is no. 

We find a very strange statement in the book of Deuteronomy after God had given the people of Israel all the laws they would need to observe to stay in fellowship with him. 

“But to this day the Lord has not given you a heart to understand or eyes to see or ears to hear” (29:4). 

Israel could not understand the things of God, nor could they truly listen to his commands in such a way that they would obey them. Why? Because their hearts were not right. 

After this verse, God tells them that, in the near future, they are going to break his covenant and fall under his wrath. And sure enough, as we read the rest of the Bible, we realize this is exactly what happens. 

So what hope did they have? What hope do we have? If we can’t follow God’s commands and stay in right relationship with him, what are they, and we, to do? 

We need new hearts. 

Thankfully, in the next chapter of Deuteronomy God makes a promise to fix our hearts. This is our text for today. 

God says that he will circumcise our hearts, so that we will love him. God himself must and will perform an inner surgery on us. He will change our hearts. 

This is what Jesus does for us through the work of the Holy Spirit. If you have put your faith in Jesus and his Gospel, then you have already experienced part of this work. We cannot believe in Jesus without this inner work of the Holy Spirit. 

God continues to work on us every day as well. He operates on our hearts daily. And the point of the operation is told to us in this verse: that we may love him with our whole hearts. 

Do you want to change your heart? Call out to God and ask him to change it. Only he can do it. 

The only other thing to do is cast all your love on God through Christ. Consider everything he has done for you on the cross. Think about the fact that he is coming back to dwell with you forever. As your love for God grows, your heart will continue to change. 

Rejoice in the Gospel, and God will rewire your heart.