Saint Publius lived a life of asceticism in the Egyptian desert during the reign of the emperor Julian the Apostate (361-363). Before a military campaign against the Persians, the emperor sent a devil to explore the way for the army to go. The venerable Publius foresaw the intent of the emperor. He stood in prayer with upraised hands, praying day and night, and blocked the path of the devil.
For ten days the evil spirit waited until the monk concluded his prayer. Unable to proceed, he returned to the emperor and reported that he had been thwarted. In a rage against Saint Publius, Julian the Apostate vowed to avenge himself on the saint upon his return from the campaign. He did not fulfill this oath, since he soon perished.
After the death of Julian, one of his military commanders distributed his effects and received monastic tonsure at the hand of Saint Publius.