Charles Ellicott Commentary Isaiah 51:23

"and I will put it into the hand of them that afflict thee, that have said to thy soul, Bow down, that we may go over; and thou hast laid thy back as the ground, and as the street, to them that go over." — Isaiah 51:23 (ASV)

You have laid your body ... —The image is startlingly bold; but our word “prostration,” as applied to the condition of a people, embodies precisely the same thought. (Compare to Psalm 129:3.) The previous words paint the last humiliation of Eastern conquest (Joshua 10:24).