Bible verses for Catholic Middle School Youth Rally t-shirts?

So this year's theme is "Seeing is Believing: Give Me Your Eyes" or "Believing is Seeing: Give Me Your Eyes" (I can't remember right now and someone just told me a few minutes ago.) and I need a bible verse pertaining to the eyes and believing to base a t-shirt design off of. Please and thank you. Pax Domini sit semper vobiscum. :) Blessings