“‘This is what the Lord of Hosts says: I took you from the pasture and from following the sheep to be ruler over My people Israel. I have been with you wherever you have gone, and I have destroyed all your enemies before you. I will make a name for you like that of the greatest in the land. I will establish a place for My people Israel and plant them, so that they may live there and not be disturbed again. Evildoers will not afflict them as they have done ever since the day I ordered judges to be over My people Israel. I will give you rest from all your enemies.
“‘The Lord declares to you: The Lord Himself will make a house for you. When your time comes and you rest with your fathers, I will raise up after you your descendant, who will come from your body, and I will establish his kingdom. He will build a house for My name, and I will establish the throne of his kingdom forever. I will be a father to him, and he will be a son to Me. When he does wrong, I will discipline him with a human rod and with blows from others. But My faithful love will never leave him as I removed it from Saul; I removed him from your way. Your house and kingdom will endure before Me forever, and your throne will be established forever.’” (2 Samuel 8b-16)
God took his servant to the woodshed. He didn’t throw him out with the trash. God’s relationship with David was different than the relationship he had with Saul. The relationship he had with Saul was like those he would later have with the kings of the Northern Kingdom of Israel: they were dependent upon performance and the contract was a limited, short term and temporary affair with no guarantees that it would ever be renewed. Sort of like the contract you make with your cell phone company: in exchange for a new phone, you agree to remain a customer for the next two years, but if you decide to leave early, then you just pay a penalty. But God’s relationship with David was like a parent’s with his child: the relationship could not be undone.
But there were still expectations. A failure to live up to those expectations would never, could never end the relationship—but it could result in uncomfortable consequences. The people might rebel. Invaders might attack. Nevertheless, no matter how bad it ever got, the house and kingdom of David would endure forever. How so? David surely thought it was a physical kingdom, with one of his descendants forever sitting on a physical throne. God understood—and later clarified in the New Testament—that his Son reigned on high in the hearts of men. The kingdom God promised David lives on in the hearts and minds of his people, or wherever two or three are gathered in his name.