Hanun's reaction to David's delegation was a deliberate act of public humiliation designed to mock the ambassadors and strip them of their dignity [ביאור שטיינזלץ]. The choice to damage specifically half of their beards and half of their clothing was not random. It reflected Hanun's conflicted view of their arrival. On one hand, the ambassadors claimed they came with good intentions to offer comfort. On the other hand, Hanun suspected their true motive was to spy on him. By punishing them in halves, he created a physical representation of the hypocrisy he believed they possessed [מלבי ם בשם מהרי״א, ביאור שטיינזלץ].
In that era, a full beard and long garments were unmistakable symbols of honor and social standing. Damaging these items was a direct attack on the ambassadors' status [מלבי״ם]. The act of shaving only half of their beards also reveals an interesting detail about the customs of the time. Because the men were forced to remain in their shame, it is clear that shaving one's beard completely was not an accepted practice. Had it been common, they could have simply shaved off the remaining half to remove the disgrace. Instead, because it was not their custom, they had no choice but to bear the humiliation until their hair grew back [רלב״ג].
As for the damage to their clothing, the primary approach among commentators is that the men wore long robes or uniforms. Hanun cut these garments exactly in half, right at the level of their buttocks, leaving the ambassadors half-naked and deeply embarrassed. A different perspective suggests that the damaged garments were specifically trousers worn to cover the private parts. According to this view, the original word for these clothes shares a root with terms related to natural bodily fluids, indicating garments worn closest to the body. Cutting these trousers in half left the men completely exposed. Yet, unlike the lasting shame of a ruined beard, the humiliation of their torn clothing could be resolved immediately simply by putting on new clothes [רלב״ג].