The average Christian defines sin by talking about behavior. For example, what is the goal of most Christian parents? Is it not to get their children to do the right things? We set up all kinds of relational, motivational, and corrective structures to constrain and direct our children’s behavior. These structures are not without value, but if this is your only response to your child’s rebellion and sin, you will leave him defenseless against sin once he leaves home and the structures are no longer there.
Beneath the battle for behavior is another, more fundamental battle— the battle for the thoughts and motives of the heart.The heart is the real or essential you. All of the ways in which the Bible refers to the inner person (mind, emotions, spirit, soul, will, etc.) are summed up with this one term: heart. The heart is the steering wheel of every human being. Everything we do is shaped and controlled by what our hearts desire.That is why the Bible is very clear that God wants our hearts. Only when God has your heart does he have you. As much as we are affected by our broken world and the sins of others against us, our greatest problem is the sin that resides in our hearts. That is why the message of the gospel is that God transforms our lives by transforming our hearts.Lasting change always comes through the heart. This is one of Scripture’s most thoroughly developed themes, but many of us have missed its profound implications. We need a deeper understanding of Proverbs 4:23, "Above all else, guard your heart, for it is the wellspring of life."