the name of Yahweh, for his name alone

Here the word "name" represents Yahweh himself. Alternate translation: "Yahweh, for he alone" (See: rc://en/ta/man/jit/figs-metonymy)

his glory extends over the earth and the heavens

The writer speaks of Yahweh's greatness as his glory being high above earth and heaven. (See: rc://en/ta/man/jit/figs-metaphor)