David knew the Messiah would die and be raised.
David knew that Christ would reign in His kingdom while David was in his tomb.
2 Samuel 7:12-13
"When your days are fulfilled and you rest with your fathers, I will set up your seed after you, who will come from your body, and I will establish his kingdom. He shall build a house for My name, and I will establish the throne of his kingdom forever.
That is why Peter makes a point in Acts 2 that David is in his tomb.
During the millennium will David be in his tomb?