Verse 1
David built houses (yes, plural) for himself in Jerusalem.
He also prepared a tent for the Ark of God. We learn in II Samuel that David desperately wanted to build a house for God; but God said "No". God points out that He is not in need of a house of cedar. Also, David had blood on his hands as a man of war (and God knew David would soon have murderous, adulterous blood on his hands).
The Ark of God comes to the City of David
He's David's directive from verse 2:
No one is to carry the Ark of God but the Levites; for the Lord chose them to carry the Ark of God and to minister to Him forever.
I Chronicles 15:2
Well, look who's been reading his sacred texts!!
When the King reads God's Word, his people don't get slain for breaking the law. Leadership comes with extra responsibility and accountability and David learned a hard lesson; but at least he learned it. Many who came before him did not. They continued to do what was right in their own eyes. Don't get me wrong; David has plenty of sin ahead of him. However, God called him after His own heart--and we can see why in scenes like this. He learned hi lesson and made proper preparations for the legal process for getting the Ark to Jerusalem.
Once again, he assembled all of Jerusalem. It seems like he had two primary, coinciding goals: get God's Ark to the capital and unify the people under God.
Then David gathered the Levites and the specific chiefs and priests in charge of the move. He made them consecrate themselves and reminded them of what happened the previous attempt when they were now following Moses' instructions.
Ryrie explains their consecration as washing, avoid defilements, and avoiding sex.
Then in distinctly David's style, he made a very big production of appointing singers and musicians to make a very big and loud worship procession. Then the names of all involved in leading that were listed.
There was joy!
God was helping!
They sacrificed bulls and rams.
This time, significantly to me, David was dignified in fine linen and walking with the Levites, not dancing and singing with the worshipers. Don't get me wrong. the singing and music is absolutely vital. But last time, David was so busy rejoicing with them that he hadn't attended to his very serious kingly duties and someone died. This time, he is directly attending to the Ark, not the celebration around it.
He's even wearing an ephod, which, I believe, mean he;s associating himself as a priest, even though he is tribe of Judah and not tribe of Levi. He is taking his responsibility to the Ark that seriously.
Michal
While the rest of the chapter is a joyful recounting of the successful journey of the Ark to Jerusalem, there is one very sour note in the final verse: Michal.
Michal was David's first wife, daughter of Saul. Given to him as a manipulation. And yet she loved him once. Then Saul's rage for David caused him to give her to another man; only to have David reclaim her. Now, full of bitterness, when all of Israel went to retrieve the Ark of God--something very near and dear to her husband. Something he had spend months and money to make happen. Micahal sat in her room, staring out her window in resentful bitterness. So that when her formerly beloved husband came dancing and rejoicing with the Ark, she despised him.
It doesn't appear to go in the depths here that it does in II Samuel, but when he comes into his home, she comes out to meet him and verbal derides him for wearing his priestly ephod and not his royal robe, even calling him naked for it. Maybe feeling slighted by being demoted to wife of priest instead of wife of King.
He does not take that well. He reminds her that it was God who chose between Saul and David and that he would celebrate God.
The scene in II Samuel ends by noting that she died childless. Which may be a reflection on God not opening her womb. But might also be interpreted that David no longer had relations with her--to her shame.
All of which worked for the greater good in the long run, as God always does, as a child of David (Judah) and Michal (Benjamin) would have further clouded the issues between to the two tribes and the eventual bloodline of Christ.