1 Samuel 17:29

25 Now the men of Israel had been saying, “Do you see this man who keeps coming out to defy Israel? To the man who kills him the king will give great riches. And he will give him his daughter in marriage and exempt his father’s house from taxation in Israel.”

26 David asked the men who were standing with him, “What will be done for the man who kills this Philistine and removes this disgrace from Israel? Just who is this uncircumcised Philistine, that he should defy the armies of the living God?”

27 The people told him about the offer, saying, “That is what will be done for the man who kills him.”

28 Now when David’s oldest brother Eliab heard him speaking to the men, his anger burned against David. “Why have you come down here?” he asked. “And with whom did you leave those few sheep in the wilderness? I know your pride and wickedness of heart—you have come down to see the battle!”

29 “What have I done now?” said David. “Was it not just a question?”

30 Then he turned from him toward another and asked about the offer, and those people answered him just as the first ones had answered.

31 Now David’s words were overheard and reported to Saul, who called for him.

32 And David said to Saul, “Let no man’s heart fail on account of this Philistine. Your servant will go and fight him!”

33 But Saul replied, “You cannot go out against this Philistine to fight him. You are just a boy, and he has been a warrior from his youth.”

Read all of 1 Samuel 17