All existing things, including the earth and its creatures and all the heavenly bodies. The universe was made by God and is sustained by Jesus Christ.
God as the Maker of all things
See also
God as the ruler of the universe
Jesus Christ, the one through whom the universe was made, now sustains all things
The title "firstborn" implies that Jesus Christ is the heir, that everything belongs to him
The universe is temporary
Future renewal of the universe
Other references to the universe