2 Samuel 19:22

Adversaries unto me. This was a time for mercy, not hard, cold justice. The occasion called for reconciliation, not a meting out of punishment upon all who had previously turned their backs upon David. The greatness and magnanimity of David was displayed on this occasion. The king attempted to win the nation back to himself by kindness and mercy. He indicated that all would be forgiven who wished to make their peace with him. With a lesser man than David there would have been much shedding of guilty blood and there would also have been much enmity as a result. In advocating a policy of retaliation the sons of Zeruiah were adversaries rather than friends of the cause of David.

This day king. Because he was king, David could afford to be merciful. If his cause had been still in doubt, sterner measures would have been in order to ensure the stamping out of opposition.