The conversion of Gallicanus, Commander-in-Chief. On the eve of his departure for a campaign against the Scythians, Gallicanus is betrothed to the Emperor Constantine’s daughter, Constance, a consecrated virgin.

When threatened with defeat in battle, Gallicanus is converted by John and Paul, Grand Almoners to Constance. He is immediately baptized and takes a vow of celibacy.

Later he is exiled by order of Julian the Apostate, and receives the crown of martyrdom. John and Paul are put to death by the same prince and buried secretly in their own house. Not long after, the son of their executioner becomes possessed by a devil. He is cured after confessing the crime committed by his father. He bears witness to the merits of the martyrs, and is baptized, together with his father.