The writer speaks to Jerusalem, which he also calls Zion, as if it were a person. The names of the city are metonyms for the people who live in it. AT: "people of Jerusalem ... people of Zion" (See: [[rc://en/ta/man/translate/figs-personification]] and [[rc://en/ta/man/translate/figs-metonymy]])
The phrase "the bars of your gates" represent the city as a whole. Yahweh will make Jerusalem secure from enemy invasion. AT: "For he protects Jerusalem" (See: [[rc://en/ta/man/translate/figs-synecdoche]])
# he blesses ... among you
The writer speaks of those who live in Jerusalem as if they were Jerusalem's children. AT: "he blesses those who live in Jerusalem" (See: [[rc://en/ta/man/translate/figs-metaphor]])
"He brings peace." Possible meanings are 1) Yahweh causes the people who live in Jerusalem to prosper materially and financially or 2) the word translated as "prosperity" means "peace" and Yahweh keeps Jerusalem safe from enemy attack.