The Jews thought that they had a behavioral problem; Jesus taught that they had a heart problem. Our behavior is often witnessed by others, and sometimes the presence of others inclines us to behave differently than we otherwise would. In contrast, our heart is hidden in a secret place where only God sees it. For this reason, Jesus cautions us to beware of the motives behind our public behavior and warns us to avoid acting differently in the presence of others because of the presence of others. Instead, we should behave in public the same way we behave in private. If our motive for obedience is anything other than to please God, then we are operating out of unrighteous motives. To advertise our piety for the applause of others displeases God and causes us to forego His applause.