Four times David was likened to an angel of the Lord. Everything he did pleased the loyal Israelites, all the Israelites that were loyal to God were loyal to him as well. He had many, many, many children. He had seven brothers. Elhanan, one of his elite knights, was also from Bethlehem, and slew evil Nephilim for the Israelites. David was given credit for this.
David ordered his men to kill a very loyal, righteous, God-fearing Amalekite soldier for the killing of Saul, the disgraced, disowned King of Israel. It was Saul's fault for not knowing or being able to commit suicide properly and putting the both of them in a terrible situation.