In the Bible, “The heart” is a phrase used in many ways. But to boil it down really quick, according to the Bible, your heart is the deepest, truest you. Therefore when Jesus said that out of the heart comes evil actions (Matthew 15:18-19), he was saying who we are determines what we do.
Jeremiah 17:9 states the heart is deceitfully wicked. In other words, our identity is corrupt. We have a false, sinful nature apart from Jesus Christ. This is the reason the gospel offers us a new heart (Ezekiel 36:26). In other words, God offers us a new nature.
So what does the Bible say about changing your heart? Christianity changes our hearts, it changes our identity, thus it changes our lives.
According the Bible, a Heart Problem Needs a Heart Solution
At the core of basic Christian beliefs is the idea that people do not sin and then become sinners, they sin because they are sinners. Over and over again the Bible points to the truth that apart from Jesus, the heart was born wicked and thus will produce wicked actions (Psalm 51:5, Matthew 7:17, Luke 6:45, John 15:5, Galatians 5:16-26).
There are many Christian books in our day describing what a Christian should be like, what we should be willing to give up, and what we should be willing to take on. These books are good. If we don’t know what to do, how can we do it? But we can never stop with a sheer description of what a true Christian should be like. If we do, we are merely preaching morality, not true Christianity.
True Christianity not only tells you what you should do, it actually gives you the power to do it; and in some ways it even gives you the benefits of doing the right thing even when you don’t do it.
When someone tells me, “We as Christians need to love the world around us. We should pray for the person who annoys us at work. We should get in the slow lane to help us develop patience. We shouldn’t be so hypocritical . . . ,” obviously they are right (except for getting in the slow lane to develop patience; that’s like telling an alcoholic to buy a bunch of booze and put it all over the house to make them stronger – that’s just dumb).
However, they haven’t helped me at all until they tell me how to do these things. Telling someone to be a good Christian without pointing them to the power of Christ is like telling a starving person not to be hungry but without giving them any food. If I am hungry, how can I not be hungry? That’s my condition. That’s what I currently am.
This is why modern wisdom such as “positive thinking” eventually becomes ridiculous. “I’m not that hungry, I’m not that hungry . . . .” Telling yourself over and over again you’re not hungry will work for about one day until your hunger just keeps getting worse and worse. Finally it will get so bad you’ll break into the nearest bag of chips and devour the first box of Twinkies you come across, filling yourself with all the wrong types of foods.
According to the Bible, the Heart of the Problem Is the Problem of the Heart
That’s what happens when you just try harder not to sin and be better while denying you have a sin problem at your core. You eventually snap and fill yourself with junk. Problems don’t go away. They need to be actively solved.
If your heart’s condition doesn’t change, which is the real problem, you’re not going to get different results by just trying harder to get different results. Who you are determines what you will do. And what you do is evidence and a reflection of who you really are (James 2:18). Until you begin to live from the new hear by remaining in Jesus, your sinful nature will continue to produce sin (John 15:5).
Charles Haddon Spurgeon, the man some people called the Prince of Preachers, said, “Repentance of the evil act, and not of the evil heart, is like men pumping water out of a leaky vessel, but forgetting to stop the leak. Some would dam up the stream, but leave the fountain still flowing; they would remove the eruption from the skin, but leave the disease in the flesh.”
Jesus doesn’t just want to forgive, he wants to solve the problem that caused the sin in the first place. He doesn’t leave us starving, expecting us to resist filling ourselves with sin. He fill us with good things so our new selves in him don’t even want the junk (Psalm 103:5).
Christianity Changes Our Lives Because Christianity Changes Our Hearts
In Galatians 5:19 it says, “The acts of the sinful nature are obvious . . . ” and then it goes on to list them. But then in verse 22 it says, “But the fruit of the Spirit is . . . ” and then it list those as well. Notice the sinful actions are attributed to our old-self controlled by the sinful nature. The good actions are not called “the fruit of the self-controlled Christian,” or “the fruit of the sin management program,” or “the fruit of the tips and techniques based in self-effort system.” They’re called “the fruit of the Spirit” because it’s not the Christian producing them but God’s Holy Spirit in the Christian. The Holy Spirit changes us.
Jesus knows that if we are the problem, we are not going to be the solution. John Stott in Basic Christianity recounts of Archbishop William Temple’s explanation:
It is no good giving me a play like Hamlet or King Lear, and telling me to write a play like that. Shakespeare could do it; I can’t. And it is not good showing me a life like the life of Jesus and telling me to live a life like that. Jesus could do it; I can’t. But if the genius of Shakespeare could come and live in me, then I could write plays like that. And if the Spirit of Jesus could come and live in me, then I could live a life like that.”
Jesus is our example, but he’s also more than that. He is the very power working in us to do what he commands.
Psalm 86:11 states, “Teach me your way, Lord, that I may rely on your faithfulness; give me an undivided heart, that I may fear your name.” We need to be taught God’s ways, but we also need him to change our hearts so we can actually do what we are being taught.
So what does the Bible say about changing your heart? Christianity changes our lives because Christianity changes our hearts.