דברי הימים א, פרק ט״ו, פסוק ג׳

King David initiates a broad national movement, gathering the people once again to complete the important task of bringing the Ark of God into Jerusalem [ביאור שטיינזלץ]. This large gathering is not formed quietly. Instead, the nation is brought together through a public proclamation, a call sent out to all of Israel [מלבי״ם].

The clear purpose of this event is to move the Ark from its current stay at the house of Oved-Edom [מצודת דוד]. From there, the people will bring it to its final destination, a special tent that David set up specifically for it within the city [ביאור שטיינזלץ].