The article didn't explain the main metaphors of the story of Ausur and Auset aka Osiris and Isis. Osiris represents Day and Sun, light energy of life, while his consort Isis represents life and nature. His brother Set, as in Sunset, represents night and desert, also the patron god of the Egyptian royalty who would have been awake after sunset when it is cooler.
The story of the death and rebirth of Osiris is how the ancient Egyptians have imagined the cycle of day and night. After Set's victory, the night comes while the Sun/Osiris is traveling below the horizon through the land of Duat, the Underworld, where he is fighting the Apep serpent representing the Chaos.
The Horus' victory over Set starts the new day, thus the child Horus, usually depicted sitting on the lap while being nursing by Isis, became to symbolize the morning sun, while Ra is the midday sun at its full power, with Atum as the evening, setting sun, and Osiris / Ausur is the sun bellow the horizon during the night.
https://www.ancient-origins.net/artifacts-other-artifacts/eye-horus-0011014