Plutarch De Iside et Osiride 38

[38] Of the stars the Egyptians think that the Dog-star is the star of Isis, ¹ because it is the bringer of water. ² They also hold the Lion in honour, and they adorn the doorways of their shrines with gaping lions’ heads, ³ because the Nile overflows

As they regard the Nile as the effusion of Osiris, ⁵ so they hold and believe the earth to be the body of Isis, not all of it, but so much of it as the Nile covers, fertilizing it and uniting with it. ⁶ From this union they make Horus to be born. The all-conserving and fostering Hora, that is the seasonable tempering of the surrounding air, is Horus, who they say was brought up by Leto in the marshes round about Buto ⁷ ; for the watery and saturated land best nurtures those exhalations which quench and abate aridity and dryness.

The outmost parts of the land beside the mountains and bordering on the sea the Egyptians call Nephthys. This is why they give to Nephthys the name of Finality, ⁸ and say that she is the wife of Typhon. Whenever, then, the Nile overflows and with abounding waters spreads far away to those who dwell in the outermost regions, they call this the union of Osiris with Nephthys, ⁹ which is proved by the upspringing of the plants. Among these is the melilotus, ¹⁰ by the wilting and failing of which, as the story goes, Typhon gained knowledge of the wrong done to his bed. So Isis gave birth to Horus in lawful wedlock, but Nephthys bore Anubis clandestinely. However, in the chronological lists of the kings they record that Nephthys, after her marriage to Typhon, was at first barren. If they say this, not about a woman, but about the goddess, they must mean by it the utter barrenness and unproduetivity of the earth resulting from a hard-baked soil.

[38] They believe likewise that of all the stars, the Sirius (or Dog) is proper to Isis, because it bringeth on the flowing of the Nile. They also pay divine honor to the lion, and adorn the gates of their temples with the yawning mouths of lions, because the Nile then overflows its banks, And as they term the Nile the efflux of Osiris, so they hold and esteem the earth for the body of Isis; and not all of it either, but that part only which the Nile, as it were, leaps over, and thereby impregnates and mixes with it. And by this amorous congress they produce Horus. Now this Horus is that Hora, or sweet season and just temperament of the ambient air, which nourisheth and preserveth all things; and they report him to have been nursed by Latona in the marshy grounds about Buto, because moist and watery land best feeds those exhaled vapors which quench and relax drought and parching heat. But those parts of the country which are outmost and upon the confines and sea-coast they call Nephthys; and therefore they give her the name of Teleutaea (or the outmost) and report her to be married to Typhon. When therefore the Nile is excessive great, and so far passes its ordinary bounds that it approaches to those that inhabit the outmost quarters, they call this Osiris’s accompanying with Nephthys, found out by the springing up of plants thereupon, whereof the melilot is one; which (as the story tells us), being dropped behind and left there, gave Typhon to understand the wrong that had been done to his bed. Which made them say that Isis had a lawful son called Horus, and Nephthys a bastard called Anubis. And indeed they record in the successions of their kings, that Nephthys being married to Typhon was at first barren. Now if they do not mean this of a woman but of a Goddess, they must needs hint that the earth, by reason of its solidity, is in its own nature unfruitful and barren.