City of God

In these times Apis king of Argos crossed over into Egypt in ships, and, on dying there, was made Serapis, the chief god of all the Egyptians. Now Varro gives this very ready reason why, after his death, he was called, not Apis, but Serapis. The ark in which he was placed when dead, which every one now calls a sarcophagus, was then called in Greek σορὸς, and they began to worship him when buried in it before his temple was built; and from Soros and Apis he was called first [Sorosapis, or] Sorapis, and then Serapis, by changing a letter, as easily happens.

It was decreed regarding him also, that whoever should say he had been a man should be capitally punished. And since in every temple where Isis and Serapis were worshipped there was also an image which, with finger pressed on the lips, seemed to warn men to keep silence, Varro thinks this signifies that it should be kept secret that they had been human. But that bull which, with wonderful folly, deluded Egypt nourished with abundant delicacies in honor of him, was not called Serapis, but Apis, because they worshipped him alive without a sarcophagus.

On the death of that bull, when they sought and found a calf of the same color—that is, similarly marked with certain white spots—they believed it was something miraculous, and divinely provided for them. Yet it was no great thing for the demons, in order to deceive them, to show to a cow when she was conceiving and pregnant the image of such a bull, which she alone could see, and by it attract the breeding passion of the mother, so that it might appear in a bodily shape in her young, just as Jacob so managed with the spotted rods that the sheep and goats were born spotted. For what men can do with real colors and substances, the demons can very easily do by showing unreal forms to breeding animals.