12 and they mourned, and wept, and fasted until even, for Saul, and for Jonathan his son, and for the people of Jehovah, and for the house of Israel; because they were fallen by the sword.
David was sincere in his mourning for Saul; and all with him humbled themselves under the hand of God, laid so heavily upon Israel by this defeat. The man who brought the tidings, David put to death, as a murderer of his prince. David herein did not do unjustly; the Amalekite confessed the crime. If he did as he said, he deserved to die for treason; and his lying to David, if indeed it were a lie, proved, as sooner or later that sin will prove, lying against himself. Hereby David showed himself zealous for public justice, without regard to his own private interest.
Matthew Henry's Commentary on 2 Samuel 1:12
Commentary on 2 Samuel 1:11-16
(Read 2 Samuel 1:11-16)
David was sincere in his mourning for Saul; and all with him humbled themselves under the hand of God, laid so heavily upon Israel by this defeat. The man who brought the tidings, David put to death, as a murderer of his prince. David herein did not do unjustly; the Amalekite confessed the crime. If he did as he said, he deserved to die for treason; and his lying to David, if indeed it were a lie, proved, as sooner or later that sin will prove, lying against himself. Hereby David showed himself zealous for public justice, without regard to his own private interest.