A chiasm is a literary structure where the words or themes of the first section of a passage are repeated in reverse order in the second. Typically whatever is in the center of the chiasm is what is being emphasized. In Ezekiel 31:7-9, God in using the defeat of Assyria as an analogy to the coming defeat of Pharaoh, shows that the magnificence of Assyria did not prevent God from judging it (Ezek 31:8).