Van Eyck’s masterpiece is a meditation on the mystery of the Holy Eucharist (the feast of Corpus Christi also originates from Flanders).

The artist uses various techniques to involve the spectator in the painting. The altarpiece, now displayed under one of the western towers, was painted for a chapel in the chevet of St Bravo’s Cathedral, Ghent. In a jewel in the morse of the cope of one of the attendant angels is a meticulously painted reflection of the stained glass window behind the viewer in the chapel. The observer stands in real space, directly related to painted, divine space.

On an altar, whose elaborate frontal is painted in similar detail, stands a very real fleecy lamb. From its pierced side gushes a geometrically precise arch of blood, falling into a chalice. A few drops of blood have fallen onto the cloth. They spread through it, in a virtuoso representation of spilled wine on fine linen.

Van Eyck, it seems, is giving us a painterly variation on St Thomas’s doctrine expressed in the propers for the Feast of Corpus Christi – symbol and tangible reality are here one and the same.

Could the carefully painted altar frontal have been a copy of the one usually placed before the altar below the painting? Did van Eyck want the viewer to make a direct connection between the Mass being celebrated and the heavenly adoration he depicts? I like to think so; but in the absence of the relevant needlework we will never know.

Mark Stevens