How do we know that God's kingdom is eternal?

The promise God makes to David in 2 Samuel 7 establishes that his descendants would lead a kingdom that lasts forever. This is specifically tied to the coming of Christ, as affirmed in Luke 1:32-33, where the angel declares that Jesus will inherit the throne of David and rule his kingdom forever. This connection between David’s lineage and Jesus' eternal kingship underscores the assurance believers have in God's unchanging plan for salvation and His ongoing sovereign rule over all creation.