TSK
Treasury of Scripture Knowledge references in NET.
“When Aaron and his sons have finished covering the sanctuary and all the furnishings of the sanctuary, when the camp is ready to journey, then the Kohathites will come to carry them; but they must not touch any holy thing, or they will die. These are the responsibilities of the Kohathites with the tent of meeting.
and commanded the people:“When you see the ark of the covenant of the LORD your God being carried by the Levitical priests, you must leave here and walk behind it.
Then David said,“Only the Levites may carry the ark of God, for the LORD chose them to carry the ark of the LORD and to serve before him perpetually.”
So David, the leaders of Israel, and the commanders of units of a thousand went to bring up the ark of the LORD’s covenant from the house of Obed-Edom with celebration.