Mass of Saint Gregory with the Appearance of Christ

A Mass in one of the niches of a church. St. Gregory is kneeling before the altar. Behind him two acolytes hold candles. Also several monks are present. One of them waves the thurible. In the foreground and to the left and right of the altar kneel lay people and some animals (a dog, a sheep and a donkey). Christ appears from heaven and descends onto the altar. From the wound in his chest flows blood, which fills the chalice. Angels and cherubins accompany him. Above Christ flies the Holy Spirit in the form of a dove. At the very top God the Father.