The phrase "the city of God" refers to Jerusalem, and represents the people who live in that city. AT: "make the people who live in Jerusalem happy" (See: [[rc://en/ta/man/translate/figs-metonymy]])
Here, the word "moved" is the same word translated as "shaken" in [Psalms v. 2](./001.md). The writer speaks of the destruction of Jerusalem by armies as if an earthquake were to destroy it. This can be stated in active form. AT: "nothing will be able destroy her" (See: [[rc://en/ta/man/translate/figs-metaphor]] and [[rc://en/ta/man/translate/figs-activepassive]])