Piero della Francesca (1415-1492) painted the Baptism of Christ, which now hangs at the National Gallery in London. Experts say that in this work the artist employed the “golden ratio” or the divine proportion, the ratio of distances in simple geometric figures.
The scene depicted relates to the moment when, as Luke describes it, “[a]fter all the people had been baptized and Jesus also had been baptized and was praying, heaven was opened and the holy Spirit descended upon him in bodily form like a dove. And a voice came from heaven, ‘You are my beloved Son; with you I am well pleased.’”
Many other artists essayed the subject, among them Andrea del Verrocchio, whose misfortune was that his pupil, a young man named Leonardo da Vinci, included an angel in the picture, a detail that drew attention away from Verrocchio’s work as a whole.
In Piero della Francisca’s painting, a dove (representing the Holy Spirit) hovers above the right hand of John pouring water over the head of Christ. All three–dove, hand and Christ–form a vertical line that divides the picture into two, the left half being further divided into two by a tree, in accordance with what is called the golden ratio.
What I understand of ratio comes from high school Algebra. Our teacher—who was one day cheerful and another day irritable—taught us how to measure the height of a tree by measuring both its shadow and mine. The relation of shadow to height should be the same for the tree and me. (Times there were when I wished I could measure our teacher’s mood, and knew the emotional ratio, whatever remained constant during his choleric and sanguine days.)
In a sermon about the Baptism of Christ, St. Gregory Nazianzen describes the relation, the ratio of Jesus to John: “The Baptist protests; Jesus insists. Then John says: I ought to be baptized by you. He is the lamp in the presence of the sun, the voice in the presence of the Word, the friend in the presence of the Bridegroom, the greatest of all born of woman in the presence of the firstborn of all creation, the one who leapt in his mother’s womb in the presence of him who was adored in the womb, the forerunner and future forerunner in the presence of him who has already come again.”
As to della Francesca’s painting, what of the tree on the left side, which divides it into quadrants? Might it not suggest some ratio, one that bears on man’s relationship with God?
There was a tree–the tree of knowledge of good and evil–in the beginning of the history of salvation. And in the fullness of time, there was another tree–the tree of the cross. Was Piero della Francesca thinking of this? Did it cross his thoughts—as now it does mine—that there might be a ratio: of man to the tree of knowledge, and of Christ to the tree of the cross?
And then the three angels in the painting, standing under the shade of the tree, differently garbed and, well, holding hands, who seem in deep thought–surely, they’re not reflecting on the number of loonies who use ballpens to those who work with pencils in computing the number of angels who can dance on the head of a pin? Likely as not, they’re expressing amazement at how, through his baptism, in the words of St. Gregory Nazianzen, Christ, “who is spirit and flesh comes to begin a new creation through the Spirit and water.”
They seem to look at me, as though wanting to communicate another ratio, the ratio of salvation–Christ is to his baptism, as I am to mine.