Let your eyes look directly forward, and let your eyelids look straight before you.
All Commentaries on Proverbs 4:25 Go To Proverbs 4
Cyril of Jerusalem
AD 386
Someone will say, “What, then, is sin? Is it an animal? An angel? A demon? What is this which infects us?” Rest assured it is not an enemy attacking from without but an evil springing up within you. “Let your eyes look straight ahead,” and there exists no evil desire. If you do not steal the property of others, robbery is at an end. Be mindful of the judgment and neither fornication nor adultery nor murder nor any wickedness will prevail over you. It is when you forget God that you begin to entertain evil thoughts and commit wicked deeds.