Plead — God at first pleads with sinners by words, but if he cannot so prevail, he will plead with them in a way by which he will overcome; by fire, pestilence and blood. All flesh — Thus he threatens to do with all the wicked Jews. The slain — Those whom God should cause to be slain.
Related Commentaries of Isaiah 66:16
Isaiah 66:16
16 For by fire and by his sword will the LORD plead with all flesh: and the slain of the LORD shall be many.