At the request of Pastor Rousselot (1823-1889), the sanctuary’s decoration provides a “theological lesson” on the Eucharist. This sacrament commemorates Christ’s sacrifice and presence in Christians’ faith.
At the very bottom of the altarpiece there is a high relief of the Last Supper carved on wood. It is the institution of the Eucharist on the eve of Christ’s death.
The Crucifixion is in the centre of the altarpiece: Christ is shown dead on the cross, the Virgin and St John stand on either side of the cross, and Mary Magdalene is kneeling at his feet.
Around the Crucifixion you can see four Old Testament scenes heralding the sacrifice of the cross and of the Mass.
Top left: Moses prays in front of the Ark of the Covenant, in which is kept a pot of manna; he legislated on rules of worship.
In the upper right, high priest Aaron immolates a lamb according to tradition.
In the bottom right, the sacrifice of Isaac by his father Abraham.
In the bottom left: Melchizedek’s bread and wine offering.
In the upper part of the altarpiece, the Virgin Mary (after whom Notre-Dame is named) is crowned by her son, Jesus Christ. His royal attributes signal his victory over death through his resurrection.
The composition draws the eye upwards towards the vaulted ceiling, indicating the path to heavenly happiness, with its angels and stars on an intense blue background.