He also leads me to the answer. The comparision is made here between the old and the new. The old covenant served as a teaching tool showing how one day the restoration of relationships between God and the believer would actually take place. This reconciliation would be by the one perfect sacrifice of His Son. The law could not accomplish this because it was too weak.
Human history proves it.
Then ten laws. Today, libraries filled with thousands of volumes of laws. It has power to teach us what is right and wrong. It has no power to change our hearts, to make us pure, to cause us to desire what is right and reject what is wrong. The old system could reveal sin.