Annunciation from the Mérode altarpiece - Campin/Flémalle

In place of the chimney fire found in, for example, the Virgin and Child in an Interior, from Campin's studio, here the painter has depicted an extinguished hearth. The only flame, the only light that can come to Mary is the one brought by the archangel Gabriel.

In front of the fireplace, Campin imagined a wooden screen pierced with holes, which is itself an allegory of painting, a wooden panel through which the eye must pass to reach the image of God: this is the principle of translatio ad prototypum, which governs the Christian theology of images.