This is an altarpiece and represents confirmation of the fullness of Titian's colouristic conception and of his original handling of light. Yet it also offers a clear political and ideological message. The painting is a votive work to cast out the plague that afflicted Venice at that time: one side are Saints Roch and Sebastian, protectors against disease, and on the other are Cosmas and Damian, who were doctors. At the centre, on the pedestal where we would expect to see a Madonna and child, is St Mark. The saint represents Venice, so the message is clear: for Venice, salvation does not arrive from Heaven above but from its innate civil virtues. Delivery from the plague is the precise task of the Republic’s government.