Deuteronomy 28:33-34, 65

The fruit of thy land, and all thy labours, shall a nation which thou knowest not eat up; and thou shalt be only oppressed and crushed alway: so that thou shalt be mad for the sight of thine eyes which thou shalt see.

And among these nations shalt thou find no ease, neither shall the sole of thy foot have rest: but the LORD shall give thee there a trembling heart, and failing of eyes, and sorrow of mind