Bless the Lord, all his works - All that he has made, animate and inanimate, intelligent and brute. It is not uncommon to call on the inanimate creation to join with intelligent beings in praising God. Compare Psalms 148:1-14. The same thing is often found in the “Paradise Lost,” and in fact occurs in all poetry.
In all places of his dominion - Wherever he reigns, on earth, or in heaven; here or in distant worlds.
Bless the Lord, O my soul - Ending the psalm as it began, and with the additional reason derived from the fact that the “universe” is called on to do it. As one of the creatures of God; as a part of that vast universe, the psalmist now calls on his own soul to unite with all others - to be one of them - in praising and blessing the Creator. He “desired” thus to unite with all others. His heart was full; and in a universe thus joyous - thus vocal with praise - he wished to be one among the immense multitudes that lifted their voices in adoration of the great Yahweh.