The Egyptian Myth of Creation celebrates the idea of the cyclical nature of life: birth, maturity, death, and rebirth. Do Isis, Osiris or Horus take part in this cycle?
In the Egyptian myths, Isis represents life and rebirth: when Set, her brother, kills Osiris (his brother and Isis' brother/husband), Isis (with the help of her sister Nephthys) gathers together the parts of Osiris that Set had strewn about the world, and with Isis' magic, she brings Osiris back to life. However, he decides to live in the underworld, becoming the ruler of that domain.
Osiris was the ruler of all the world. It is said that he taught humankind agriculture. When he is killed, he is revived by his wife Isis, however, he travels to the underworld, and there he remains:
To the Egyptians, Osiris represents life, death and resurrection.
The Egyption creation myths explain how the earth was fashioned from chaos. The first god to emerge was Ra (or Re). In turn, he gave birth to gods who ruled over the elements, such as air, earth and sky. Ra also created mankind.
Ra creates several gods including Shu and Tefnut. They give birth to Geb and Nut. While Ra takes Nut to wife, Nut and Geb are drawn to each other. Ra finds out and punishes his wife so she cannot see Geb or give birth to her children—that she...
...should never give birth to Her young in any month of any year.
However, Thoth, the Self-Created helps Nut by creating days that are not a part of the 360-day year:
These days did not rest within any month, nor any year, and thus Nut was able to bear Her children, one on each day.
In this way, Nut can give birth and not break Ra's decree against her. In the five days she is free of Ra's punishment, she gives birth to: Osiris, Isis, Set (or Seth), Elder Horus, and Nephthys. While these characters are associated with things such as life, rebirth, death, etc., they are not presented as taking part in the creation story, but are themselves part of the creation story of Egypt.
The Ancient Egyptians based every aspect of their lives upon their mythology, which described how the world was created and is sustained by their gods. Osiris, Isis, Set, Nephthys, and Horus are considered to be the oldest of the Egyptian gods, and they play a significant part in the cyclical creation myth.
Osiris plays perhaps the largest part in the cycle of birth, maturity, death, and rebirth in that he is described in the mythology as having been killed by his brother Set and then dismembered, his pieces scattered about the world. After this, he is reassembled by his sister and lover, Isis, who represents life in the Egyptian mythology. Osiris, then, experiences birth—like his siblings, he is the son of Geb and Nut, the earth and sky—followed by maturity, death, and ultimately rebirth. This archetype, of the god who is killed and is reborn, is one perpetuated in many cultures across the globe. Subsequently, Osiris descends to rule over the underworld.
Horus, specifically Horus the Younger, is raised secretly to protect him from his uncle, Set, and is depicted growing to manhood and then challenging his uncle for the rule of the land. It is in Horus that the maturation part of the cycle is most clearly depicted. He also, moreover, represents the rebirth of order and the land: when Osiris is reassembled by Isis, they mate and give birth to Horus, completing the cycle that began with Osiris's birth.
Egyptian mythology is based on patterns that are repeated over the course of time. The mythology sequence speaks of a perpetual cycle of events occasioned by order, chaos, and renewal. The sequence repeats itself in a variety of settings including creation, life, and in the environment.
Osiris becomes king of the underworld after he is killed by his brother Set. Osiris is also identified as a static body with Ra (sun god) representing his soul. Although Ra travels during the day across the sky, he has to go back to Osiris in order to rejuvenate and continue his journey. The event represents the renewal powers held by Osiris.
Osiris and Isis represent order; they successfully persuaded the Egyptians to adopt agriculture that supported Egypt’s civilization.
Osiris and Isis give birth to Horus, representing rebirth.