Mass of St. Gregory

Robert Campin's Mass of Saint Gregory depicts the devotional legend in which Pope Gregory the Great, doubting the real presence of Christ in the Eucharist, was reassured by a vision of the Man of Sorrows appearing on the altar during Mass. The subject was among the most popular devotional images in late medieval northern Europe, often used on altar panels and diptychs to stimulate meditation on the Eucharist. Campin's version applies his characteristic physical directness to the miraculous vision, making the bleeding Christ appear with the same corporeal reality as the human figures in the composition. The work belongs to the tradition of Flemish devotional painting created to accompany liturgical practice.

The scene is set within a church interior rendered with Campin's characteristic spatial precision, the celebrant and altar surrounded by the instruments of the Passion painted with the meticulous detail of Netherlandish realism.