Eyes are the window to the soul so they say. Perhaps that is why they are so important in symbolism. They tell you so much.
There was a parish in Cleveland that recessed lighting in its very high and flat ceiling. Around one of the lights a giant eyeball was painted. This was the eye of God that tells us He is all knowing, all seeing, every present. (Now that I think if it, that eye was kind of creepy, which is probably why I liked it so much. It has since been painted over and the building closed.)
The eye in a Triangle is a symbol of the Trinity. Accompanying it will often be an areola. If the eye is alone, it is usually a depiction of God the Father.
Where eyes are looking is often very telling. Eyes cast down might be grief, humility, or shame depending on the greater context. Eyes looking to heaven might be prayer, inspiration, pleading, or the eyes of someone seeing a vision (think of St. Stephen.)
Eyes directed at you means the painting or statue is trying to tell you something directly – even if it is just “be holy.” Eyes looking elsewhere are trying to direct you to something else more important. It might be to an action or a person that is supposed to be the focus. Of course blindness and the ability to see, whether real or symbolic are very important in the spiritual life.
Very little direction to where one’s eyes are supposed to be are given in the General Instruction of the Roman Missal. One direction that is given is in the Roman Canon (or Eucharistic Prayer one.) When the priest says, “With eyes raised to you . . .” the rubric states that the priest is to look up toward heaven. However, where a priest looks is very important during the Mass. A lot of misinformation can be given by where he chooses to look, so powerful are our eyes. For years I thought that the Eucharist prayer was directed to the congregation because the priest made such a big point about staring at the people as he said the prayers. In fact, almost none of it is. It is directed to the Father and we are supposed to be joining the priest in this action. Not even the phrase, “Take this all of you and eat it,” is directed to the congregation. We are reminding the Father what the Son said in order that God will make the bread and wine into the Body and Blood, Soul and Divinity of Jesus.
There are a few places that the priest SHOULD look at the people because he is directly addressing them. These are such times as when he says, “Let us pray,” or “Behold the Lamb of God,” or giving the homily or proclaiming the Gospel. (Though I understand it is difficult not make the wrong impression at times since we are standing face to face even when we are not addressing each other. But good efforts should be made.)
Eyes on a plate are a symbol of St. Lucy. Prior to her martyrdom she was tortured by having her eyes gouged out.
In iconography the eyes are extremely important. They are a window to heaven and as we gaze at the image of the saint, one should “look through their eyes” into heaven itself and contemplate things of God.
Much more could be written but this is just a taste (just think of what is done to eyes by Hollywood especially in spookier movies! That is how important they are.) But this gives you a taste (or should I say a glimpse?)