It is said that eyes are the window of one's heart. It is because eyes reveal one's inner heart like the lens of a camera that can capture the world. One's nature and goodness are embedded in his eyes, so we can feel his heart and nature through his eyes. His deeds are different according to with what kind of eyes he sees the world. A good-hearted person sees everything with goodness and practices goodness, but an evil-minded person practices evils.
"A man with an evil eye hastens after wealth and does not know that want will come upon him." (Proverbs 28:22)