In these passages is the account of David being told of Saul’s death by an Amalekite who witnessed the battle on Mount Gilboa. The Amalekite told David that he had encountered Saul leaning on his sword. Saul wanted to kill himself but was unable. The Amalekite claimed that he killed Saul at Saul’s request.
The Amalekite brought Saul’s crown and bracelet to David. However, David had the Amalekite killed for killing God’s anointed. David mourned greatly for Saul.
I believe that the Amalekite expected David to rejoice at Saul’s death and that David would reward him. However, David did not rejoice over the death of his enemy.
The Bible says that we should not delight when our enemies are harmed or killed. That is not the attitude that God wants us to have. Like many right actions, this one is contrary to our natural desire for vengeance against those who harm us. However, the Bible says that we should not seek vengeance. We must trust God to avenge the wrong that may have been done to us.