Saint Gregory the Great was pope from 590 to 604. He is admired as a Doctor of the Church for his great reforms of the early liturgy. In the window, we see him wearing the papal tiara, which was typical attire for the Holy Father from the eighth century until the reign of Paul VI in the 1960s. We also notice a dove on the pope’s shoulder as he writes. This symbol comes from a story from Peter the Deacon, who reported that when composing his Homilies on Ezekiel, Gregory was accompanied by a dove who whispered the words of the homilies to him. Whether this is true or not, we can be certain that the Holy Spirit was with Pope Gregory in his work, just as the Spirit remains with the successor of Saint Peter today.