2 Samuel 21:15-17

Again there was war between the Philistines and Israel. David and his men went out to fight the Philistines, but David became tired. Ishbi-Benob, one of the sons of Rapha, had a bronze spearhead weighing about seven and one-half pounds and a new sword. He planned to kill David, but Abishai son of Zeruiah killed the Philistine and saved David’s life. Then David’s men made a promise to him, saying, “Never again will you go out with us to battle. If you were killed, Israel would lose its greatest leader.”