St. Ambrose assures Gratian of victory, declaring that it has been foretold in the prophecies of Ezekiel. This hope is further stayed upon the emperor’s piety, the former disasters being the punishment of Eastern heresy. The disasters here alluded to are the rout of the Roman army, in 378 a.d., at Hadrianople, and the miserable death of the Emperor Valens, who took refuge in a hut, which was surrounded and fired by the Goths, the emperor perishing in the flames. This reverse was regarded by the orthodox as a judgment upon the Arianism of Valens and others in high places. The book closes with a prayer to God, that He will now show His mercy, and save the army, the land, and the sovereign of the faithful.