The writer speaks of the kings' fear as if it were a person who caused the kings and their armies to tremble. AT: "There they trembled with fear" (See: [[rc://en/ta/man/translate/figs-personification]])
The writer speaks of the kings' fear as if it were the pain that a woman experiences in childbirth and speaks of that pain as if it were a person. The verb may be supplied from the previous clause. AT: "pain took hold of them, as when a woman is in labor" or "they became afraid, like a woman is afraid of experiencing labor pains" (See: [[rc://en/ta/man/translate/figs-metaphor]] and [[rc://en/ta/man/translate/figs-personification]] and [[rc://en/ta/man/translate/figs-ellipsis]])