Saint Isaac of Dalmatia (died May 30, 383) was a Byzantine monk who was imprisoned for denouncing the Roman emperor Valens for the heresy of Arianism and predicting that Valens would "die in flames" because of his actions. Soon after, Valens went to war with the Goths but was defeated and died in a fire after taking refuge in a barn. Valens' successor Theodosius I released Isaac, outlawed Arianism and reopened the Catholic churches closed by Valens. Wikipedia
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