The angel finishes speaking to John about the prostitute and the beast.
# is
Here "is" stands for "represents." (See: [[rc://en/ta/man/translate/figs-metaphor]])
# the great city that rules
When it says that the city rules, it means that the leader of the city rules. AT: "the great city whose leader rules" (See: [[rc://en/ta/man/translate/figs-metonymy]])