These panels illustrate two episodes from the Legend of the True Cross. The first shows the Emperor Heraclius defeating Chosroes II, the last King of the Sasanian Empire, whose armies had seized the True Cross following their conquest of the Levant. The second shows Heraclius restoring the True Cross to the city of Jerusalem, following its recapture by the Byzantines. The Emperor is depicted in his undergarments as requested by an angel, who bade him to humble himself. Upon stripping off his armor, the Cross became miraculously light and the gates of the city sprung open of their own accord.