Dimensions: 37 x 45 cm.

The altarpiece, one of the most grandiose of the Quattrocento altars, was executed after the decision of Cosimo de' Medici in 1438 to transfer to Cortona the triptych which served as main altar of the convent church. It depicts, in the front, the kneeling Sts Cosmas and Damian, then in the second row, from the left: Sts Lawrence, John the Evangelist, Mark, Dominic, Francis and Peter the Martyr. It is assumed that the figure of St Cosmas is the likeness of Cosimo de' Medici. In the lower center a Crucifixion with golden background can be seen.

This picture was placed on the right lateral side of the altarpiece. Justinian sleeps while Sts Cosmas and Damian enter his chamber trailing patches of soft cloud. They replace his corrupted leg with a healthy one. The room is Spartan but the variety of light-sources and Angelico's close observation give it interest. Light floods in from outside through the window on the left, illuminating its own frame and parts of the swags of curtain. Exterior space is indicated not only by the window but by the door opposite it, from whence comes more light. From the front left outside the picture comes the third source of light, which produces a broad diagonal sweep across the right wall. The curtain provides the rectangular backdrop parallel to the picture surface which is common to each of these predella panels, and also hints at more, obscured space behind it. The container hanging from a nail on the side of the bed, the glass and decanter, the slippers and the simple three-legged stool, all provide the constituents of a closely observed still-life.