In 1374 in the small Flemish village of Middelburg-in-Flanders, a man named Jan van der Beeck — known publicly to be living in grave sin — presented himself for Communion in defiance of his pastor's repeated warnings. As the consecrated host touched his tongue, it turned to a piece of bleeding flesh in his mouth. He collapsed and died at the Communion rail.
The bloodied host was preserved and venerated at Middelburg until the religious wars of the 16th century, when it was translated for safe-keeping to the church of Saint-Jacques (Sint-Jacobskerk) in Leuven, where it remains. The bishop of Bruges confirmed the cult.