A divine promise for the future of the nation establishes a direct connection between God and the people, while also revealing the identity of their future leader. While this vision is largely viewed as straightforward and self-explanatory [רד״ק, ביאור שטיינזלץ], the specific details carry deeper meaning regarding how this future will unfold [מצודת דוד].
The declaration of His renewed relationship with the people signifies that God will take an active role, working directly to save and rescue them. Furthermore, the promise of a prince named David does not refer to the historical king returning to rule. Instead, it points to the future Messianic king who will be born from his descendants.
The concluding divine statement serves as a seal of absolute certainty. Because God has decreed these events, their fulfillment is completely guaranteed.