The phrases "let loose his hand" is an idiom that means to act quickly. Also, the phrase "cut me off from this life" is a euphemism for killing him. Alternate translation: "that he would act quickly and cut short my life" or "that he would act quickly and end my life" (See: [[rc://en/ta/man/translate/figs-idiom]] and [[rc://en/ta/man/translate/figs-euphemism]])