After the creation of the world, the first five gods were born of the union of Geb (earth) and Nut (sky) and these were Osiris, Isis, Set, Nephthys, and Horus. Osiris, as the first born, assumed rule as Lord of the Earth, with Isis as his queen and consort. He found the people of Egypt uncivilized and lawless and so gave them laws, culture, religious instruction, and agriculture. Egypt became a paradise under Osiris’ rule where everyone was equal and there was abundant food as the crops were always plentiful. Set was jealous of his brother’s success and grew resentful. Their relationship deteriorated further after Nephthys, Set’s wife, disguised herself as Isis and seduced Osiris, becoming pregnant with the god Anubis. Set had a beautiful coffin made to Osiris’ exact height and then threw a grand party where he presented this box and told the guests that whichever of them fit in it most perfectly could have it as a gift. When Osiris lay down in the coffin, Set slammed the lid on, fastened it shut, and threw it into the Nile, where it was carried away down river.
Osiris’ body traveled out to sea and eventually his coffin became lodged in a great tamarisk tree growing near Byblos in Phoenicia. The tree grew quickly around the coffin until it completely contained it. The king of Byblos, Malcander, came to the shore with his wife Astarte and admired the tree and the sweet scent which seemed to emanate from it. He ordered the tree cut down and brought to his palace as an ornamental pillar for the court, and there Osiris remained, trapped inside the coffin within the pillar, until he died.
Isis had meanwhile left Egypt in search of her husband and eventually came to Byblos, disguised as an older woman, where she sat down by the shore and cried for her missing husband. She was invited to the palace by the royal handmaidens who had come to the shore to bathe and there ingratiated herself to the king and queen so she was asked to be nursemaid for their young sons. Isis tried to make the younger boy immortal by bathing him in fire and, when Queen Astarte discovered this, she was horrified. Isis then revealed herself as the goddess and the king and queen promised her anything she wanted if she would only spare them. She requested only the pillar – which they swiftly granted to her.
Osiris as the kind and just ruler, murdered by his resentful brother, who comes back to life is the most popular and enduring image of the god.
After leaving the court, Isis cut Osiris from the tree and carried his body back to Egypt where she hid him from Set in the swampy region of the Nile Delta. She left him to go gather herbs to make a potion to return him to life, leaving her sister Nephthys to guard the body. While she was gone, Set learned of his brother’s return and went out to find his body. He managed to get Nephthys to tell him where it was, and when he found it, he hacked it into pieces and scattered it across the land and into the Nile. When Isis returned, she was horrified but quickly composed herself and went to work finding the pieces of her murdered husband. With Nephthys’ help, she recovered all of the body parts except the penis, which had been thrown into the Nile and eaten by the oxyrhyncus fish, which is why this fish was forbidden food in ancient Egypt.
Isis was able to revive Osiris and, once he was alive, she assumed the form of a kite and flew around him, drew the seed from his body into her own, and became pregnant with a son, Horus. Even though Osiris now lived, he was incomplete and could no longer rule the land of the living. He withdrew into the afterlife where he became Lord and Judge of the Dead. Isis, fearing what Set might do to her son, hid Horus among the swamps of Egypt until he was grown. At that point, Horus emerged as a mighty warrior and battled Set for control of the world. In some versions of the story, Set is killed but, in most, he is defeated and driven from the land. The chaos Set had unleashed on the world was conquered by Horus, who restored order, and then ruled with his mother.
Source: Ancient History (www.ancient.eu)