Jesus said that the eye is the window to the soul.
“The eye is the lamp of the body. If your eyes are healthy, your whole body will be full of light.”
— Matthew 6:22 (NIV)
He also said that we are the light of the world.
“You are the light of the world. A city set on a hill cannot be hidden.”
— Matthew 5:14 (ESV)
Maybe when you let the light from the sun in through your eyes, it penetrates your soul, giving you Thumos, spirit.