‘The King-elect’s lament over the death of the King’ (2 Samuel 1:1-27)

The book of 2 Samuel continues the story of 1 Samuel, where in chapter 31, King Saul met a grisly end by his own hand. 2 Samuel opens with the news of Saul’s death reaching King-elect David. It may be that the news-bearer presented the report on Saul’s death to David in the hope of some reward, but all it achieved was distress and grief to David and a swift execution for the news-bearer! Why such a response from David? And why such distress? And why such a poetic lament for Saul after all that Saul did for David? And what can we learn from David’s response to the news of Saul’s death?