The heavens are thine - Are thy work; and, therefore, thy property - the highest conception of property being that which is derived from creation. It is also implied here that as all things belong to God, he has a right to dispose of them as he pleases.
The earth also is thine - The earth itself, as made by thee; all that the earth produces, as having sprung out of that which thou hast made. The entire proprietorship is in thee.
As for the world - In the use of this word, the earth is spoken of as inhabitable, meaning that the earth and all that dwell upon it belong to God.
And the fulness thereof - All that it produces; what constitutes its enireness. That is, the earth itself considered as earth, or as a mass of matter; and all that springs from it; all that constitutes the earth, with all its mountains, seas, rivers, people, animals, minerals, harvests, cities, towns, monuments - the productions of nature, the works of power, and the achievements of art. Compare the notes at Psalms 24:1.
Thou hast founded them - They all have their foundation in thee; that is, thou hast caused them all to exist. They have no independent and separate basis on which to rest.