The Annals and the Histories · Hist. 4.82

Vespasian thus came to conceive a deeper desire to visit the sanctuary of Serapis, that he might consult the God about the interests of his throne. He gave orders that all persons should be excluded from the temple. He had entered, and was absorbed in worship, when he saw behind him one of the chief men of Egypt, named Basilides, whom he knew at the time to be detained by sickness at a considerable distance, as much as several days' journey, from Alexandria. He enquired of the priests, whether Basilides had on this day entered the temple. He enquired of others whom he met, whether he had been seen in the city. At length, sending some horsemen, he ascertained that at that very instant the man had been eighty miles distant. He then concluded that it was a divine apparition, and discovered an oracular force in the name of Basilides.

Cornelius Tacitus · trans. Church & Brodribb, 1876
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