How do we know the teachings of Christ are higher than the Old Testament law?

In Matthew 5, Jesus clarifies that He did not come to abolish the law but to fulfill it, demonstrating that His teachings go beyond mere external adherence to the law's commandments. For instance, He expounds the command against murder to include anger and insults, and extends adultery to include lustful thoughts. This deepens the understanding of God's law, emphasizing that the spiritual intent behind the commandments is paramount. Thus, Christ magnifies the law, raising the standard for His followers and showing that true obedience flows from an inner transformation.