What is the meaning of the 'fullness thereof' in Psalm 24?

The phrase 'fullness thereof' in Psalm 24:1 encompasses all that God has created and provides. This includes not only the physical earth but all resources, life forms, and sustenance that flow from it. God's ownership extends to everything within creation, implying a responsibility on humanity to manage it wisely and generously. It underscores the sovereignty of God in maintaining and providing for His creation throughout history. Thus, recognizing the 'fullness' as God’s property invites believers to gratitude and a sense of duty in stewardship, as everything stems from His sovereign will.