1 Samuel 17:26-30

Then David spoke to the men who were standing by him, “What will be done for the man who kills this Philistine and removes the disgrace [of his taunting] from Israel? For who is this uncircumcised Philistine that he has taunted and defied the armies of the living God?” The men told him, “That is what will be done for the man who kills him.” Now Eliab his oldest brother heard what he said to the men; and Eliab’s anger burned against David and he said, “Why have you come down here? With whom did you leave those few sheep in the wilderness? I know your presumption (overconfidence) and the evil of your heart; for you have come down in order to see the battle.” But David said, “What have I done now? Was it not just a [harmless] question?” Then David turned away from Eliab to someone else and asked the same question; and the people gave him the same answer as the first time.