The two organ shutters come from the church of Santa Maria di Campagna in Piacenza .There is a majestic architecture, functioning as background for the prophets Isaiah, on the left, and for David, on the right. The two protagonists lean symmetrically on high pedestals of ionic columns, on which Latin epigraphs stand out, predicting the coming of the Saviour. Isaiah holds a scroll in his hands, which symbolizes his book.