16 For with fire and with his sword the LORD will execute judgment on all people, and many will be those slain by the LORD.

Read Isaiah 66:16 Using Other Translations

For by fire and by his sword will the LORD plead with all flesh: and the slain of the LORD shall be many.
For by fire will the LORD enter into judgment, and by his sword, with all flesh; and those slain by the LORD shall be many.
The LORD will punish the world by fire and by his sword. He will judge the earth, and many will be killed by him.