This intimate triptych, which dates from about 1425, is traditionally known as the Mérode Altarpiece, after the family that owned it during the nineteenth century. It illustrates the moment when the archangel Gabriel announces to the Virgin Mary that she has been chosen by God to be the mother of Christ. The patrons of the painting gaze upon this miraculous event from one of the side panels, while Joseph, busy at his carpenter's bench, occupies the other wing. Campin's fascination with the natural and domestic world dominates his telling of the sacred story. He meticulously renders even the smallest details in an innovative technique combining translucent oil overlay on water-based opaque pigments. The resulting optical effects enhance Campin's interpretation of the Virgin's private chamber as an affluent fifteenth century interior filled with household appointments and goods similar to those that the patron would have known. Yet Campin was essentially guided in his choice of objects by the symbolic needs of the story. The brass laver, for example, signifies Mary's purity, as does the Madonna lily in the maiolica pitcher. As an object of private devotion, this painting would have been integrated into the furnishings of the owners' private quarters, where its hinged wings could be opened and closed according to the daily cadence of private prayers or following the traditions of the Christian calendar.