Gris lidis admits to her husband that their son has been abducted. The Marquis tries to use the swords on the wall, but they disappear. Gris lidis takes her husband by the hand and they kneel before the alter piece and pray. The cross above the altar changes into a glowing sword and the Marquis takes the weapon. Gris lidis prays to St. Agnes to return and bring back her son.
Trumpets indicate the victory of good over evil.
The Devil takes his defeat with charm and promises to live the rest of his life as a hermit. The scene and opera end with the strains of the Magnificat.