The Stavelot Reliquary: Detail, Constanine's dream

Circa 1156
Champlevé and cloisonné on copper gilt
Morgan Library, New York

The medallions of inner face of the left wing illustrate the story of the Emperor Constantine, while those on the right are based on the legend of his mother Helena's discovery of the "True Cross." This is the bottom medallion on the left. The curtain on the left and the triple arch with domes set the scene in the bedchamber of Constantine's palace. As he sleeps an angel points to the cross in the sky and speaks the words written on the scroll, in hoc signo vinces, "in this sign you shall conquer." The crown hanging from the central dome signifies Constantine's future rule over a reunified Roman Empire.

View the entire reliquary.

Source: this page at Wikimedia Commons.