Sister-wife of Osiris. The cow was sacred to her; and she is represented with two long horns from one stem at the top of her head. She is said to have invented spinning and weaving. (Egyptian mythology.)
Inventress of the woof, fair Lina [flax] flings The flying shuttle thro' the dancing strings. Taught by her labours, from the fertile soil Immortal Isis clothed the banks of Nile.
Milton, in Paradise Lost, names Osiris, Isis, and Orus amongst the fallen angels (book i. 478).
Diodoros confounds her with the Moon, Demeter, and Juno. Plutarch confounds her with Athena (Minerva), Perseph one (Proserpine), the Moon, and Tethys. Apuleius calls her the mother of the gods Minerva, Venus, Diana, Proserpine, Ceres, Juno, Bellona, Hecate, and Rhamnusia [Nemesis].
Lockyer says, “Isis represents the idea of rising or becoming visible. Osiris of disappearing.” Thus the rising moon, a rising planet, the coming dawn, etc., is Isis; but the setting sun, the waning moon, a setting planet, evening, etc., is Osiris.
“Now the bright moonbeams kissed the water, ... and now the mountain
and valley, river and plain, were flooded with white light, for mother
Isis was arisen.” —
Isis was the mother of Horus (the rising sun), and is represented as nursing him.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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