My friends we all know we do evil. Why do we continue this way? We do not wish to sin. It is because we are not able to change. We try to do good, but we do evil. This is because we have a sinful heart. Perhaps you steal something with your hand. It will profit you nothing to cut off your hand. You may steal again tomorrow. Stealing comes from inside of us. It is really from within, not from your hands. Thus it is with all sin. When your hands are dirty you can wash them in water and make them clean. Can you wash your sinful heart with water and cleanse it? No, even if you bathe many times, you keep on sinning. Our bad words come from the evil in our hearts. Our bad thoughts come from the evil in our hearts.
Have you ever seen a leopard? (Name another animal if more appropriate). There are spots on its body. Can the leopard wash them off by washing very hard? No. Why does he not have the power to take off his spots? Because they are not fastened onto the outside of his body. They come out from the inside. The leopard cannot change the way he is made.
Likewise our sins are not something which are on the outside. The evil we do only shows there is evil in our hearts. How can we change our hearts? Many people say, "Stop doing bad things." But they do not tell us how to change our evil hearts.
Can a leopard moo like a cow? Can he say, "From now on I will eat only grass?" No, only God can change a leopard. Likewise, we cannot say, "From now on I will do only good." Only God can change our sinful hearts and make us want to do good. If a thief is punished, perhaps he will stop stealing. But who can take from him the desire to steal? Only God can do this. My friend, I have good news for you. There is One who can take away the evil from our hearts. He can make them to be good. He is the only Son of God. His name is Jesus. He has power to give each of us a new, clean heart. With it we will have power to do only good things.
Jesus wants to change your heart now. You do not need to wait. I will tell you what to do. Tell your sins to Him, and turn away from them. Ask Jesus to change your bad heart and make it good. Ask Him to put His own Spirit in you. He will do this if you turn from evil and trust in Jesus.
Optional: Some day Jesus is coming back to this earth. At that time He will change all leopards so that they will not eat meat any more. They will eat grass like cows. People will no longer fear them. This will be a wonderful thing. By this you see that Jesus is very powerful. To change a leopard is a great thing, but to change a person's heart is even greater!