1 Samuel 18:5-9

Whatever Saul asked David to do, David did it successfully. So Saul made him a commander over the men of war, an appointment that was welcomed by the people and Saul’s officers alike. When the victorious Israelite army was returning home after David had killed the Philistine, women from all the towns of Israel came out to meet King Saul. They sang and danced for joy with tambourines and cymbals. This was their song: “Saul has killed his thousands, and David his ten thousands!” This made Saul very angry. “What’s this?” he said. “They credit David with ten thousands and me with only thousands. Next they’ll be making him their king!” So from that time on Saul kept a jealous eye on David.