Addressed to the Emperor Theodosius after the massacre at Thessalonica. St. Ambrose begins by stating his reasons for not having met the Emperor on his return to Milan. He then mentions the sentiments of the bishops with regard to the slaughter at Thessalonica, and points out that repentance for that deed is necessary to obtain forgiveness and a victory over the devil, the instigator to that crime. St. Ambrose could not offer the sacrifice in the Emperor’s presence, and, as truly loving the Emperor, grieves and yet hopes.