en_tn/pro/10/13.md

on the lips of a discerning person

"Lips" represents what a person says. Alternate translation: "in what a sensible person says" (See: rc://en/ta/man/jit/figs-metonymy)

a rod is for the back

"Rod" represents strong, physical punishment and "the back" represents the person who receives the punishment. Alternate translation: "a person who has no sense needs forceful punishment" (See: rc://en/ta/man/jit/figs-metonymy and rc://en/ta/man/jit/figs-synecdoche)