The Hieronymus Altar

Closed, this altarpiece shows the Mass of Saint Gregory, the legend in which Christ appeared above the altar while the pope was saying Mass, and on a rail in that scene the painter wrote Anno Domini 1511 twice. It has two pairs of wings, which is unusual, so it opens in two stages. The first opening brings out eight saints, among them Willibrord, the missionary to the Frisians, the Emperor Henry and Elizabeth of Thuringia.

Open it fully and Saint Jerome sits enthroned in the centre, with a kneeling man and woman and their two daughters, church fathers on the left wings and apostles on the right. Nobody knows who the couple were. The marks painted on the altar may point to the Schönbeck family, and from 1541 to 1627 it stood in St Mary's church in Stendal, in northern Germany, a long way from Amsterdam. The throne Jerome sits on is trimmed with Renaissance ornament, among the earliest painted in the northern Netherlands. An old German inventory described the whole object simply as an altar with Saint Jerome's image that opens twice.