Here "dust of Jacob" is a metaphor that speaks of the number of Israelites as if they were as numerous as the specks of dust. This rhetorical question can be translated as a statement. AT: "There are too many Israelites to count. No one could count even a fourth of them because there are so many." (See: [[rc://en/ta/man/translate/figs-rquestion]] and [[rc://en/ta/man/translate/figs-metaphor]])
It is understood that this will be a peaceful death. This can be stated. AT: "the peaceful death of a righteous person" (See: [[rc://en/ta/man/translate/figs-explicit]])