This speaks of a rich person depending on his wealth as if his wealth were a fortified wall that protects him. AT: "The wealthy person depends on his wealth as a city depends on its fortified wall" (See: [[rc://en/ta/man/translate/figs-metaphor]])
This speaks of the rich person believing his wealth will keep him safe like a high wall keeps those inside a city safe. AT: "he thinks it protects him as well as a high wall" (See: [[rc://en/ta/man/translate/figs-simile]])