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He had no military training, and no skill with the elite weapons of war, but when he saw a battle that needed to be won he didn’t hesitate to engage. Against all odds, and armed only with the knowledge of how God had strengthened him before, a sling and a few small stones, David faced a vicious enemy. 1 Samuel 17 gives the account of how David heard the Philistines taunting God and the armies of Israel, how no soldiers were willing to fight the Philistine champion, and how David—depending on the Lord—won the day. Being only a boy, David was met with resistance when he volunteered to fight. King Saul told him he was not able (1 Sam. 17:33).
David’s response was brilliant (and helpful): “The Lord who delivered me from the paw of the lion and from the paw of the bear, He will deliver me from the hand of this Philistine” (1 Sam. 17:37). And of course, we know the rest of the story.
David’s attitude toward serving God provides an excellent example for us today, especially as we consider spiritual gifts. David lived in a different age, and the Holy Spirit was not operating in exactly the same way—He would temporarily strengthen people for specific tasks, and there is no evidence that He indwelt people then as He does in the church age. Because David wasn’t dealing with “spiritual gifts,” I use his episode with Goliath as an example, but we have to be careful not to take the analogy too far.
In any case, David was certain he would be able to function successfully in a future endeavor only because of how God provided for him in similar past endeavors. He exhibited no fear in looking forward to the task at hand because of his history with God. But as far as we know, David had no special revelation from God to that point. As far as the Bible reveals, God did not promise David He would deliver him from the lion or the bear—or Goliath. But yet David was confident, and he proclaimed to Goliath, “I come to you in the name of the Lord of hosts, the God of the armies of Israel, whom you have taunted” (17:45).