两国交战，不斩来使两国交战，不斩来使[liǎng guó jiāo zhàn bù zhǎn lái shǐ]1.■When two countries are at war, the delegates must not be killed.; It has not been permitted that when war comes between two countries those who come and go as messengers can be killed.; Messengers should neither be beheaded or hanged.; Two states at war will not kill each others' envoys.