Icons can help us visualize what cannot be easily explained. They hover between two worlds, rendering in color and form what cannot be easily grasped by the intellect, somehow making the invisible visible. As such they are considered visual equivalents of Sacred Scripture.
Probably the best-known of all icons is that of Andrei Rublev. Rublev’s icon of the Trinity was painted around 1410 in Moscow. It is a visual depiction of the mysterious story from the Book of Genesis of the three angels who visited Abraham. Abraham serves them a meal, and it seems that these ‘angels’ are metaphor for the three persons of the Blessed Trinity. In the background we see a house in the upper left and a tree in the center. A rocky hillside lies in the upper right hand corner. The whole composition forms a great circle around the table, drawing our attention to the chalice-like bowl at its center, a clear reminder of the altar at communion.
Although the ‘angels’ are shown as equals, each one wears different clothing. On the right the Holy Spirit has a garment of sky blue and a cloak of green, for the Creator Spirit breathed in heaven and on earth. In the center the Son wears a garment of reddish-brown the color of earth and a cloak of heavenly blue, for in his person he unites heaven and earth; he is truly human, truly divine. The Father is clothed in a garment of indescribable fabric that changes with the light, for no one has seen the Father. The light that shines about the heads of all three is pure white, the whiteness of untouchable light.
The Father looks forward, raising his hand in blessing to the Son; as if to say, “This is my beloved Son, listen to him.” The hand of the Son points to the Spirit. And we viewers complete the circle. Each Person holds a staff for their journey, since they accompany us on our journey across the face of the earth.
This great icon invites us into the depth and intimacy of life in God. Led by the Spirit, we are invited to live in the shadow of the Son of God, resting beneath his tree of life as we journey home to the house of our Father.
See :www.sacredheartpullman.org/documents/2017/8/Trinityicon.pdf. Excerpted from Father Emmanuel's homily for the Solemnity of the Most Blessed Trinity.