It was David's question, "Who am I?" in 2 Samuel 7, that made him worthy of being king of Israel and that distinguished him from his predecessor.  David fully recognized that he was, in fact, no one before God and that he had nothing for which he could boast.  His humility was astonishing in light of his military record.  He brought down Goliath, he led many military victories for Saul, and he had now assumed the place of leadership over the nation.  And yet he still recognized that he was nothing.  What a great perspective that we all need to embrace.  It's not about our gifts and talents, it's not about our ingenuity and our victories.  What matters is whether or not we exist to make God's Name great.  God exalted David because of David's humility, and even today, few people in the world do not know who he was.  And yet the greatest thing he's known for is also the reason why God allowed his name to be exalted: he was humble, and he passed on glory to the Lord.