Samuel’s account of David bringing the ark back to Jerusalem is a bit puzzling (see 2 Samuel 6). It’s fundamentally the same story as in 1 Chronicles 13 and 15, but in Chronicles we have the reason for Uzzah’s death: the ark was not supposed to be carried on a cart of any kind, but was to be borne by the Levites.
Keep in mind that we are reading Chronicles in its chronological order. It is one of the last books of the Old Testament to be written and it was composed after the exile. Chapter fifteen points to at least three things: First, the importance of the Levites. When the Ark was no longer being carried from place to place, but was situated in Jerusalem, there would be little for three Levite clans to do (see their assignments in Numbers 4). This is probably why, after the exile, the Levites were held in such low esteem (see Nehemiah 13:10). Though they may have little to do, these people are highly regarded by God and Israel is bound to support them and respect them. Second, the chapter tells us the new assignments for the Levites (since the temple was making their old assignments obsolete). And third, it tells us who was responsible for those assignments: David.
This brings up a matter of biblical interpretation: Where did David get the authority to make these assignments? There appears to be no real directive from the Lord, but on the other hand, these men should have important substantive work to do. David recognized both and made assignments. Without divine directive, David made the decision. Silence was permission. The debate continues to rage over the authority of silence in scripture. Is it prohibitive or permissive? It is best to let silence be silence. Unless you are a king taking the part of a priest (note David dresses as both here), you have no authority to make this decision.
Two points remain: Notice the preparation that went in to bringing the ark to Jerusalem. Notice that everyone consecrated themselves (spent time in preparation holiness – perhaps prayer, sacrifice for sin, whatever needed to be done that one might present his life cleansed before God). Note also that they put on their best clothes (note “fine” linen 15:27). Preparation for worship should be from the inside out, but should include the outside. Appearing before the Lord without thoughtfulness to appearance is a disgrace.
Finally, notice Michal, Saul’s daughter. All Israel was rejoicing in worship before the Lord. She, however, like a lot of spoil-sport Christians, had something stuck in her craw (the Chronicler doesn’t even tell us what it was) and refused to join in the celebration. The command to rejoice with those who rejoice is a command to deny self and come before the Lord with singing and praise. If something isn’t going your way, don’t let it spoil your worship or the worship of others. Get over yourself and rejoice that at least, you are one of the people of God.