Romans 7:9: I Was Once Alive Apart From The Law, But When The Commandment Came, Sin Came Alive And I Died
 I was once alive apart from the law, but when the commandment came, sin came alive and I died. (ESV)
I am not a doctor. Nor do I play one on TV. I can calculate that the distance between a person's head and their heart is roughly twelve inches. The distance between the head and the heart in a spiritual sense might as well be thousands of miles. There are many people who only have an understanding in their heads. That understanding never reaches their heart.
Let's look at Paul himself. We know from his own account in the New Testament that the Apostle Paul was a "Pharisee of Pharisees." When it came to head knowledge of the Law there was no one who could compare. In Philippians 3:5 Paul gives a list of all his qualifications regarding the Law. He even refers to himself as blameless as to righteousness under the Law.
Head knowledge. This is what Paul is talking about when he says that he was once alive apart from the Law. He is saying that he did not have a proper understanding of the Law. Even though he knew all the words written in the Law, he had not allowed the Law to write it's principles in his heart. The Law had not traveled the twelve inches from his head.
When the commandment came . . . There was a moment when the Law came alive in his heart. At that point he knew just how much of a sinner he was. Jesus himself had to knock him off his donkey to get his attention. Sin came alive. He now knew he was a sinner. Sin brought guilt, and an acknowledgment of spiritual death. He needed to reborn by faith in Jesus Christ.
Twelve inches can be a very long distance. You may have read the Word of God. You may have even heard of the message of salvation. Has the knowledge of salvation moved from your head to your heart? Open your heart to the truth and place your faith in Jesus Christ.