This phrase refers to the directions east, where the sun rises, and west, where the sun sets. The writer uses these two extremes to represent everywhere on earth. AT: "everywhere on earth" (See: [[rc://en/ta/man/translate/figs-merism]])
The writer speaks of God as if he were a light that shines. This refers to God causing people to know about his glory. AT: "God's glory shines like a light" (See: [[rc://en/ta/man/translate/figs-metaphor]])