Thou shalt not be afraid for the terror by night; nor for the arrow that flieth by day;
The word picture behind "nor for the arrow" is "to cut off from harvest".
It is the enemies intent to destroy the harvest in our lives by peppering the harvest field with his fiery darts.
Ephesians 6:16 Above all, taking the shield of faith, wherewith ye shall be able to quench all the fiery darts of the wicked.
The Lord of the harvest (our shield of faith) is intent on protecting His harvest in us.