There was a woman caught in the act of adultery. An angry mob was standing over her as she lay in the dirt. Jesus stooped down and wrote in the sand. The Pharisee's thought, "This is our right. This is our law. This is our duty." 

The Old Testament collides with New Testament: stoning vs. freedom, law vs. grace, mercy vs. judgment. Jesus must have been pondering the Old and the New, pondering what He was about to do. He must have been thinking...Do you understand people? Here, you are about to see My greatest glory!