How do we know Christ's kingdom is different from earthly kingdoms?

Christ's kingdom is characterized by its spiritual and everlasting qualities, distinguishing it from all earthly kingdoms. Jesus declared, 'My kingdom is not of this world' (John 18:36), highlighting that His reign does not depend on temporal power or authority. Unlike earthly kingdoms, which rise and fall, Christ's kingdom was set up by God and is sustained eternally through His sovereign will. Scriptures indicate that all worldly empires pass away, but Christ's words will never pass away (Matthew 24:35). Thus, while earthly empires may pursue dominance, they ultimately fade, unlike the everlasting kingdom of our Lord, which is centered on the hearts of His people and is guaranteed by divine promise (Psalm 145:13).