This exclamation emphasizes that a word spoken at the right time is very good. AT: "a word that a person speaks at the right time is very good" (See: [[rc://en/ta/man/translate/figs-exclamations]])
The writer speaks of a lifestyle that results in life as if it were a path that goes upward towards life and of a lifestyle that results in death as if it were a path that leads down to the place of the dead. (See: [[rc://en/ta/man/translate/figs-metaphor]])