The young David, a singer of God's praises, would come to set up temple worship as a mature man. He was a great sinner, and a great repenter. The Psalms give us a detailed account of his inner dispositions. All of David's great accomplishments look forward to an even greater reality, which is seen in God's promises regarding a "son of David". The Gospel of Mathew, chapter 22, explicity refers back to this promise.
We see the depth of God's promises to David, through the prophet Nathan, in 2 Samuel 7. "Moreover the Lord declares to you that the Lord will make you a house. When your days are fulfilled and you lie down with your ancestors, I will raise up your offspring after you, who shall come forth form your body, and I will establish his kingdom". 1 Chronicles 17 repeats the promises of 2 Samuel, emphasising the events that are yet to come.
In the promises to David, a Messianic hope arises. This occurs despite David's shortcomings and failures. His profound spiritual yearning and great repentance made him a man after God's own heart. As Christians, we too are sinners. Like David, we too can look forward to the promises that await and present blessings available to us.