1 Samuel 17:34-40

But David said to Saul, “I, your servant, have been keeping my father’s sheep. When a lion or bear came and took a sheep from the flock, I would chase it. I would attack it and save the sheep from its mouth. When it attacked me, I caught it by its fur and hit it and killed it. I, your servant, have killed both a lion and a bear! This uncircumcised Philistine will be like them, because he has spoken against the armies of the living God. The LORD who saved me from a lion and a bear will save me from this Philistine.” Saul said to David, “Go, and may the LORD be with you.” Saul put his own clothes on David. He put a bronze helmet on his head and dressed him in armor. David put on Saul’s sword and tried to walk around, but he was not used to all the armor Saul had put on him. He said to Saul, “I can’t go in this, because I’m not used to it.” Then David took it all off. He took his stick in his hand and chose five smooth stones from a stream. He put them in his shepherd’s bag and grabbed his sling. Then he went to meet the Philistine.