David had earlier served as an armor bearer (a personal assistant who carried a soldier’s weapons) to Saul (1 Samuel 16:21).
run me through: This is one of many similarities between the death of Abimelech during the time of the judges (Judges 9) and Saul, Israel’s first national king (see Judges 9:54). In both stories, a wounded leader asks someone else to kill him rather than die in shame.